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Spinor
January 28th, 2011, 08:10 PM
Do you like math? Are you good at math? Do you need help with your math homework? Do you want to see what good of a lifestyle it is to be a Mathematheist Mathematician? The join this club and exercise the joy of Mathematics!

What are to be the topics of this club:

How wonderful you think mathematics is
Neat tips and tricks in mathematics
Little math-related "Did you know?"s
Math Jokes
Help with concepts in mathematics
Help with Mathematics homework
Applications of Mathematics to Engineering and Science History of mathematics (Although not many will probably care >__>)


Anybody can come on in and ask for help with Math homework. For this, you don't have to have to like mathematics.

However, if you like math and want to be recognized for active conversations, you should probably join as a full-pledge member. This is simple and can be done by filling this out:

Username:
Overall Education Level:
Mathematics Education Level (Or most recent/advanced math subject):
Do you think you can be asked for help in your level or lower?:

Just for fun~ You can also just say you want to be a Full-pledge member.

Full-pledge Members:

[B]AdvancedK47 ; 10th Grade ; AP Calculus AB (School); Yes;
Otherworld9) ; 4.0, so I think I'm straight A's....oh, I am. ; ??? ; Yes ;
Lightning ; Undergrad ; Third Year Uni ; Yes ;
BlooMilk C. ; 8th/9th Grade ; Algebra ; Yes ;
Sammyskitty ; 11th Grade ; ??? ; Yes ;
smile! ; Uni Freshman ; Calculus II ; Probably ;
Murasaki_Paz28 ; 12th Grade ; Calculus ; Yes ;
Snow Phoenix ; 12th Grade; Calculus II ; Yes;
I like Pokemon (...) ; Year 11 ; Calculus(?) ; Yes;
Midnight Bear ; 12th Grade ; Calculus(?) ; No ;
meerfall ; Year 11 ; Higher Level (IB?) ; Yes ;
pikagirl3 ; Uni Freshman ; Algebra 2/Advanced Functions/Modeling/Discrete Math ; Yes;
Shiny Meowth ; 10th Grade ; [Some crazy crap above] Multivariable Calculus ; Yes;
Pokemon Trainer Touko ; Year 9 ; [some crazy crap above] Multivariable Calculus ; Yes
NurseBarbra ; <Irish> 4rd Year (10th Grade) ; ~Precal/Calculus (?) ; Yes ;
Drekin ; High School ; Calculus (?); Yes;
Alakazam17 ; 4th Year Uni ; Uni Level 3rd Year ; Yes
Lifes-A-Beach ; 9th Grade ; Pre-Calculus ; No
Bela ; Undergrad ; What? ; Yes
Renii ; Undergrad ; Calculus ; Yes
Drakow ; Finished Undergrad ; Bachelor of Science in Mathematics ; Yes


Remember to follow the forum and global rules. Now lets

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   \      talk(math(talk))
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___math(talk) = 0___

Otherworld9)
January 31st, 2011, 06:00 PM
Username-Otherworld9)
Overall Education Level-4.0, so I think I'm straight A's....oh, I am.
Mathematics Education Level-I'm an 8th grader, and currently taking Algebra Honors.
Do you think you can be asked for help-Yes, I've been asked for help daily, so yes.
What is the Derivative of 3X2?....I feel stupid, but I'm only in Middle School. :paranoid: 6x

I want to be a full pledged member for as long as I live.

Cherrim
January 31st, 2011, 06:15 PM
Username: Lightning
Overall Education Level: In midst of an undergrad degree
Mathematics Education Level: some second-year university courses :3
Do you think you can be asked for help in your level or lower?: Yup, though I may need a refresher on what things are. XD
What is the derivative of 3X^2?: 6x
Favourite math pick up line: I wish I were a derivative so I could lie tangent to your curves.

You cannot have a math club without math pick up lines!!! 8D

BlooMilk C.
January 31st, 2011, 06:32 PM
Username: BlooMilk C.
Overall Education Level: 8th or 9th grade.
Mathematics Education Level: Pre-Algebra, but I know most topics in Algebra.
Do you think you can be asked for help in your level or lower?: Yes.
What is the derivative of 3X2?: 6x(we just did linear functions, so the rest is Wikipedia)
Math catchprase 8D: Depressing lives are like pi, they need to be terminated.
Also, I want to join as a full-pledge memeber.

Maraala
January 31st, 2011, 07:32 PM
Username: Sammyskitty
Overall Education Level: 10th grade
Mathematics Education Level: Currently taking Algebra II
Do you think you can be asked for help in your level or lower?: Yes, I am like super amazing in Geometry whenever I remember how to do the stuff
What is the derivative of 3X^2?: 6x

I want to be a full-pledged member bro

Spinor
January 31st, 2011, 07:48 PM
Hmm... plenty of members already ^__^ I was soo expecting you, Erica

And I really have tried your pickup line there before... needless to say those things are fails until you check out math majors >__>

smile!
January 31st, 2011, 07:51 PM
Requesting joinage 8D

Username: smile!, but you can call me Arc if you want (long story)
Overall Education Level: Uhh, tbh, I'm not quite sure what level of the education in my country would be equivalent to yours. I'm guessing, around 12th grade?
Mathematics Education Level: Currently taking Calculus I.
Do you think you can be asked for help in your level or lower?: Mhmm.. Probably.
What is the derivative of 3X2?: I had to search the meaning of derivative >.> I feel so lame! XD Uh, but yeah, I'm more used to y'. Anyway, 6x.


Math catchprase 8D: Depressing lives are like pi, they need to be terminated.

XD That's funny.

Uhh, math catchphrase? Can't think of any right now. I vaguely remember something about pi, but I can't recall the exact wordings. Though, what my maths teacher once said, (sounds something like this)
If the temperature of a town is 0o Celsius today, and the temperature of tomorrow will be twice colder than today, then what is tomorrow's temperature?

Murasaki_Paz28
February 1st, 2011, 04:09 PM
Username: Murasaki_Paz28,, but you can jus call me Murasaki for short :)
Overall Education level: 11th grade
Mathematics Education Level: Already took... pre-algebra, algebra 1 honors, geometry, and algebra 2. Going towardz Pre-cal then Cal 1
Do you think you can be asked for help in your level or lower: Bad memory but i can try :P
Srry i dont get what everybodiez answering 3X2=6X,, i dont member what derivative meanz if i even learned it,, bad memory like i said :(
I guezz full pledged member plz since everyone iz already...

Cherrim
February 1st, 2011, 04:46 PM
*pats* My high school curriculum didn't introduce derivatives until the second half of the grade 12 calculus/functions course so it's not weird if you haven't seen it before. :3

Snow Phoenix
February 1st, 2011, 08:03 PM
Username: Snow Phoenix
Overall Education Level: 11th Grade, GPA = 3.94. I regret the mistakes I made when I took High School classes in middle school @-@
Mathematics Education Level: I take Calculus at a community college via dual enrollment. I started off taking Pre-Algebra in 6th, Algebra 1 in 7th, Geometry in 8th. Algebra 2 in 9th, and then College Algebra, Plane Trig., and Pre-Calculus via Dual Credit. Dual credit classes are a semester each.
Do you think you can be asked for help in your level or lower?: Yes :3 I tutor Netto every now and then <3
What did Pi say to i and what did i say back to Pi?: Err... I'd say something, but I'm probably overthinking things @-@

Spinor
February 1st, 2011, 10:24 PM
*pats* My high school curriculum didn't introduce derivatives until the second half of the grade 12 calculus/functions course so it's not weird if you haven't seen it before. :3

Actually, in the high school I go to, a lot of people are ahead in their math studies. There are like double the seniors in the Calculus AB classes than in the Pre-Calculus classes. There's ALMOST pure Seniors in the Calculus BC class and the Statistics class. Both classes barely fit the one period XD. And I say almost because I've seen Juniors taking those classes as well. Not only that, I know a Junior who took Calculus BC as a sophomore, which is hopefully exactly what I'll be doing. Note this is RARE. XD

The only difference is... he's Asian and I'm Mexican :X

So yes, by Junior year I'll be taking Calculus III and modern Algebras... if the guys at the uni I'm in for concurrent let me, anyways >__> I'll be pissed if they don't let me.

Regeneration
February 2nd, 2011, 02:35 AM
Sign me up! Even though I detest mathematics. ^_^

Username: Regeneration
Overall Education Level: 10th grade?
Mathematics Education Level: Everything except calculus Algerba, Trigonometry, Geometry.
Do you think you can be asked for help in your level or lower?: Of course!
What did Pi say to i and what did i say back to Pi?: You're incomplete without me. >D

Archer
February 2nd, 2011, 04:23 AM
I'll get around to joining properly at some point, but I just finished enrolling in my undergrad uni course today. Including Mathematics IA and IB.

Cherrim
February 2nd, 2011, 09:47 AM
Actually, in the high school I go to, a lot of people are ahead in their math studies. There are like double the seniors in the Calculus AB classes than in the Pre-Calculus classes. There's ALMOST pure Seniors in the Calculus BC class and the Statistics class. Both classes barely fit the one period XD. And I say almost because I've seen Juniors taking those classes as well. Not only that, I know a Junior who took Calculus BC as a sophomore, which is hopefully exactly what I'll be doing. Note this is RARE. XD

The only difference is... he's Asian and I'm Mexican :X

So yes, by Junior year I'll be taking Calculus III and modern Algebras... if the guys at the uni I'm in for concurrent let me, anyways >__> I'll be pissed if they don't let me.
I think you are a bit of an outlier in that regard. :P Most schools I know of aren't like that at all.

Otherworld9)
February 2nd, 2011, 06:53 PM
Sorry to change things...but it isn't strange to find an 8th grader in an Algebra Honors class, right? It's completely normal, right? (note that Algebra and Algebra Honors aren't the same...Algebra Honors is ahead.)

Spinor
February 2nd, 2011, 08:53 PM
Sorry to change things...but it isn't strange to find an 8th grader in an Algebra Honors class, right? It's completely normal, right? (note that Algebra and Algebra Honors aren't the same...Algebra Honors is ahead.)

If you went to my high school, you'd fit right in, actually XD I can't exactly speak from other point of views. Although my high school only has Pre-AP and AP programs, not Honors.

If you were Asian, it'd be strange you'd be so behind

DAWJ
February 3rd, 2011, 12:55 PM
Sorry to change things...but it isn't strange to find an 8th grader in an Algebra Honors class, right? It's completely normal, right? (note that Algebra and Algebra Honors aren't the same...Algebra Honors is ahead.)

Not at all. When I was in 8th grade, I also took algebra honors. Now I'm in 10th and is currently taking Trig.

(I am sorry if I am not allowed to post here)

I like Pokemon (...)
February 3rd, 2011, 12:59 PM
Username: I like Pokemon (...)
Overall Education Level: I'm in Year 10 in England. I'm 14, going on 15.
Mathematics Education Level: Not much at all. Recently, we learned Sine and Cosine rule. I'm still rather young, so I haven't gotten much education. I'm self teaching (pre) calculus, though.
Do you think you can be asked for help in your level or lower?: Definitely, yes. I'm used to helping students in my class, and lower. Hell, if I know the topic, I might be able to help those higher XD.
What did Pi say to i and what did i say back to Pi?: "Get real", "Be rational".

Oh, I would LOVE to be a full-pledged member.

Oh, and Arc, I feel slightly betrayed T.T

BlooMilk C.
February 3rd, 2011, 03:47 PM
If you went to my high school, you'd fit right in, actually XD I can't exactly speak from other point of views. Although my high school only has Pre-AP and AP programs, not Honors.

If you were Asian, it'd be strange you'd be so behind
This would also be normal at my school XD, or maybe even below average since we do have a lot of seventh graders in Geometry :/. I'm planning on taking an Algebra Honors course online for this program this year which will count as a high school credit.(I'm planning on taking Pre-Calculus in ninth grade, maybe with a dash of Calculus). I was planning on taking Algebra and Geometry next year at my school, but then I got into the talent identification program I wanted to and they offered the course, and I'll even get a high school credit for it, so I can take Geometry and Trigonometry next year for eighth grade so I can catch up to where I should be, according to my school :3
Also, here's a history of math anecdote that you won't care about. Did you know that the earliest evidence of written mathematics dates back to the Sumerians, who adopted a basic number system, made multiplication tables, dealt with geometric exercises, and did division problems?

"The tablets also include multiplication tables and methods for solving linear and quadratic equations. The Babylonian tablet YBC 7289 gives an approximation to √2 accurate to five decimal places."(Wikipedia)

Sagiri
February 3rd, 2011, 06:10 PM
Username:
Midnight Bear

Overall Education Level:
Eleventh grade, 4.0.

Mathematics Education Level:
Algebra 2, Geometry, Pre-Calculus

Do you think you can be asked for help in your level or lower?:
I could, because I'm really good at math, but I wouldn't advise asking me. I make a terrible teacher.

I wish I were a _______ so I could lay tangent to your curves:
Derivative. I'm sad to say that I had no idea (still in Pre-Cal), and just googled it.

smile!
February 4th, 2011, 03:16 AM
Username: I like Pokemon (...)
Overall Education Level: I'm in Year 10 in England. I'm 14, going on 15.
Mathematics Education Level: Not much at all. Recently, we learned Sine and Cosine rule. I'm still rather young, so I haven't gotten much education. I'm self teaching (pre) calculus, though.
Do you think you can be asked for help in your level or lower?: Definitely, yes. I'm used to helping students in my class, and lower. Hell, if I know the topic, I might be able to help those higher XD.
What did Pi say to i and what did i say back to Pi?: "Get real", "Be rational".

Oh, I would LOVE to be a full-pledged member.

Oh, and Arc, I feel slightly betrayed T.T

I thought you might drop by sooner or later 8D Glad to see you here :D
Why do you feel betrayed? XP

Sine and cosine rule, as in sin a/a = sin b/b or as in lim (x->0) sin h/h = 1?
Self teaching... whoa

I still remember your aim to study everything you'd learn in college now and when you do get to college, you're going to annoy your lecturer with your weird questions. XD

Be rational, nice. XD

MeerFall
February 4th, 2011, 04:45 AM
Username: meerfall
Overall Education Level: year 10
Mathematics Education Level: (surrpose to be) higher
Do you think you can be asked for help in your level or lower?: sure wynaut?
I wish i was a improper fraction so i can contain a great deal of you!

if you are an acute angle you are more then you seem
if you are an right angle you know where to turn
if you are an straight line you are as bright as the sun
if you are an obtuse angle you are big and full of ideas
if you are a reflex angle you can reach your true poltensal by beliving in yourself
if you are a 360 degree angle you are all of the above and more!

smile!
February 4th, 2011, 07:52 AM
I found a quote about maths and... love. XD

Math tells us 3 of the saddest love stories:
Of parallel lines, who are never meant to meet.
Of tangent lines, who were together once then parted forever.
And of asymptotes, who could only get closer and closer, but could never be together.

I like Pokemon (...)
February 5th, 2011, 06:48 AM
I thought you might drop by sooner or later 8D Glad to see you here :D
Thanks to Zam.
Sine and cosine rule, as in sin a/a = sin b/b or as in lim (x->0) sin h/h = 1?
Self teaching... whoa
In school, the first one. I've learned about the second one on my own, it's to do with the Squeeze theorem, right? I wonder if I can remember enough to teach someone else the lim(x->0) sinx/x =1
I still remember your aim to study everything you'd learn in college now and when you do get to college, you're going to annoy your lecturer with your weird questions. XD
I'm slowly getting there.
At the moment, my aim is to do precalc, calc, maybe trig as well. If possible, I'd LOVE to go over non-euclidean geometry, or topology in general.
I wish i was a improper fraction so i can contain a great deal of you!

if you are an acute angle you are more then you seem
if you are an right angle you know where to turn
if you are an straight line you are as bright as the sun
if you are an obtuse angle you are big and full of ideas
if you are a reflex angle you can reach your true poltensal by beliving in yourself
if you are a 360 degree angle you are all of the above and more!
Aww, those are awesome.

Also, can someone explain to me how maths is taught in USA? Because it's very different from the English system, it seems.

DAWJ
February 5th, 2011, 08:15 AM
Also, can someone explain to me how maths is taught in USA? Because it's very different from the English system, it seems.

Well In my high school you first learn Algebra in 9th Geometry 10th Trigonometry 11th and pre calc 12th. (or if your like me Algebra in 8th, Geometry in 9th, Trigonometry 10th, Pre calc 11th, and I think calc 12th.

Cherrim
February 5th, 2011, 11:14 AM
How's it taught in the English system?

In Canada, math doesn't branch out into separate topics until grade 12 (last grade). We learn a combination of algebra, geometry, trig, etc. until grade 11 and then it branches to... I forget what it is here in Ontario now. When I was in HS it was Calculus, Discrete Algebra, and Data Management. I think they merged the Discrete course and the Calculus course now (wtf).

I like Pokemon (...)
February 5th, 2011, 12:54 PM
Well In my high school you first learn Algebra in 9th Geometry 10th Trigonometry 11th and pre calc 12th. (or if your like me Algebra in 8th, Geometry in 9th, Trigonometry 10th, Pre calc 11th, and I think calc 12th.
Ah, okay, that's a bit... odd. Is that ALL you learn in each grade?
How's it taught in the English system?
Throughout the year, we all learn different things. I'm only in year 10 (equivalent to... I THINK 9th grade) and yet I've already done trigonometry.
I wouldn't be able to properly explain how it works, though, since it seems to change JUST for my year group.
In Canada, math doesn't branch out into separate topics until grade 12 (last grade). We learn a combination of algebra, geometry, trig, etc. until grade 11 and then it branches to... I forget what it is here in Ontario now. When I was in HS it was Calculus, Discrete Algebra, and Data Management. I think they merged the Discrete course and the Calculus course now (wtf).
Well, actually, thinking about it, that's quite similar to what we do. But I don't know if it splits off in Year 13 (last grade for us).

pikagirl3
February 5th, 2011, 03:17 PM
math O.O

I LOVE MATH :D

May I join?

Username: Pikagirl3
Overall Education Level: 12th Grade in High School
Mathematics Education Level: regular math, Algebra I and II, Geometry (although not that good at geomertry ^^;), Advanced Functions and Modeling, and Discrete Math.
Do you think you can be asked for help in your level or lower?: Yuppers ^^
I wish I were a _______ so I could lay tangent to your curves: Derivative ^^

Another Math Joke: (cause EVERYONE LOVES JOKES!)
-What do you get if you divide the circumference of a jack-o-lantern by its diameter? PUMPKIN PI XD

Spinor
February 7th, 2011, 09:24 PM
Also, can someone explain to me how maths is taught in USA? Because it's very different from the English system, it seems.
Generally, 9th graders take Algebra I. In 10th grade, some schools elect Algebra 2, and others elect Geometry. 11th graders take the one not taken. In Texas, a course in Math modeling can be taken BEFORE Algebra 2 to satisfy the 4 credit requirement without taking math above Algebra 2. Otherwise, 12th Grade is most generally Pre-Calculus or Trigonometry. Pre-Calculus is more dominant. In the US, The College Board also has an AP program which allows schools to include Calculus AB, Calculus BC, and Statistics as classes. The state of Texas approves these AP courses for high school credit, allowing people to graduate with up to 7 math credits.

In my case, I'll be brooming Multivar Calculus, Vector Calculus, Differential Equations, Analysis, Non-Euclid Geo, and Topology before graduating from High school ^__^ Hopefully. Of course, this means I had to concurrently enroll with an university because there doesn't seem to be any high school that offers anything above Calculus II or a second course relating to Statistics.


In Canada, math doesn't branch out into separate topics until grade 12 (last grade). We learn a combination of algebra, geometry, trig, etc. until grade 11 and then it branches to... I forget what it is here in Ontario now. When I was in HS it was Calculus, Discrete Algebra, and Data Management. I think they merged the Discrete course and the Calculus course now (wtf).
;_; Ever since 8th grade ended, I've never been able to imagine a life without subjects split apart. Specialization and even choice was pretty good.

Another Math Joke: (cause EVERYONE LOVES JOKES!)
-What do you get if you divide the circumference of a jack-o-lantern by its diameter? PUMPKIN PI XD
That'd be a nice thing to tell during Halloween XD

And wow, so many people are joining already ^__^ So glad there's a significant population with an interest in math.

ShinyMeowth
February 8th, 2011, 01:15 PM
Even with AK47's explaination I still don't get how Mathematics is taught in the US. Etymologically, Precalculus means everything before Calculus, which would include 1st-grade education, like addition of single-digit numbers. Yet apparently people have somehow limited it to something between Algebra and Calculus, but adding the split of Algebra to Algebra I and Algebra II just confuses me even more.

On topic now, I love Mathematics. That's why I am definitely going to join this group.


Username: ShinyMeowth
Overall Education Level: 9th grade
Mathematics Education Level: No idea what course this would apply to, since I've been studying at home, but I have studied Calculus up to triple integration, in Cartesian, Cylindrical and Spherical coordinates, and am currently studying Probability.
Do you think you can be asked for help in your level or lower?: Sure, always glad to help.
I wish I were a _______ so I could lay tangent to your curves: Derivative.

Anyway, Now that I have finished watching every Pokemon episode aired so far, 6 hours per day have been freed in my life. I plan to use these hours to study more, and I am planning to study, and finish number theory and group theory before I get to the 10th grade.

Anyway, I would like to bring up a topic of conversation, what do you think of teachers teaching us incorrect rules that are to be removed or disproved later on? I personally have told my teacher off many times, but still she insists that negative numbers have no square root. My opinion is the same opinion I have about reproduction. Teachers should tell their students the truth, while leaving out unnecessary details. Teaching them something that is incorrect and even insisting on it when somebody refuses to take it? That is terrible teaching in my opinion.

Otherworld9)
February 8th, 2011, 01:38 PM
Anyway, I would like to bring up a topic of conversation, what do you think of teachers teaching us incorrect rules that are to be removed or disproved later on? I personally have told my teacher off many times, but still she insists that negative numbers have no square root. My opinion is the same opinion I have about reproduction. Teachers should tell their students the truth, while leaving out unnecessary details. Teaching them something that is incorrect and even insisting on it when somebody refuses to take it? That is terrible teaching in my opinion.

I agree with you on your method of choice, on how teachers teach you something that isn't true to begin with, or actually incorrect later on. Some people just take it, and then wonder how they got a question wrong when they completely did what they were taught? I think teachers should either go over their notes/lessons, or just tell the truth.

Cherrim
February 9th, 2011, 09:50 AM
I disagree with insisting on it--if someone disagrees with it, teachers should go with the flow and sort of explain ahead a little bit if anyone's interested before going back to the curriculum.

In the case of negative fractions, I can see why they'd teach it that way. Quite often in the maths and sciences, they'll gloss over a lot of details and teach the general blanket rules before they start teaching the exceptions. I learnt that you couldn't take the root of a negative number and then a few years later (or later in the semester or the next year... I forget when I learnt square roots xD), we learnt about i and imaginary numbers. But for the most part, my experience is that a lot of people are only in math because their school requires it and for a LOT of people, tossing ~imaginary numbers~ into the mix just sounds silly and they can't grasp the material as easily so early on, or they just lose interest because "now it's getting ridiculous". :/ Sounds like you just have a bad teacher who thinks they have to follow the curriculum rigidly and with no wiggle room.

(Relatedly, I know I learnt about imaginary numbers in 11th grade math but apparently it's not even in the high school curriculum in my province anymore and I think that is unacceptable, nevermind just coming back to it later. <_<)

I like Pokemon (...)
February 9th, 2011, 03:06 PM
Generally, 9th graders take Algebra I. In 10th grade, some schools elect Algebra 2, and others elect Geometry. 11th graders take the one not taken. In Texas, a course in Math modeling can be taken BEFORE Algebra 2 to satisfy the 4 credit requirement without taking math above Algebra 2. Otherwise, 12th Grade is most generally Pre-Calculus or Trigonometry. Pre-Calculus is more dominant. In the US, The College Board also has an AP program which allows schools to include Calculus AB, Calculus BC, and Statistics as classes. The state of Texas approves these AP courses for high school credit, allowing people to graduate with up to 7 math credits.
That... just sounds complicated.
The English system has a lot less room for choice, but we tend to cover a good variety of non-specific branches of mathematics. And then it depends on what course you take in university.

And wow, so many people are joining already ^__^ So glad there's a significant population with an interest in math.
I completely agree with you there.
Even with AK47's explaination I still don't get how Mathematics is taught in the US. Etymologically, Precalculus means everything before Calculus, which would include 1st-grade education, like addition of single-digit numbers. Yet apparently people have somehow limited it to something between Algebra and Calculus, but adding the split of Algebra to Algebra I and Algebra II just confuses me even more.
I think "Pre-calc" is more specific to "the things you'll need to learn before proper calculus, ignoring basic things that you've probably learnt like addition."

Anyway, I would like to bring up a topic of conversation, what do you think of teachers teaching us incorrect rules that are to be removed or disproved later on? Teaching them something that is incorrect and even insisting on it when somebody refuses to take it? That is terrible teaching in my opinion.
Ah, yes, I definitely have an opinion on this.
I always HATE it when my teacher says that something can't be done "you can't subtract a bigger number from a smaller number/you can't square root a negative number/etc." and then next year they contradict themselves.
If I were a teacher, I would specifically mention this but I wouldn't go into much detail, instead telling the student "if you want to know more, you can research it or ask me after lesson, but you won't need to know for this module". This way, students who WANT to know this learn it, and those who don't need to know it now, won't.
(Relatedly, I know I learnt about imaginary numbers in 11th grade math but apparently it's not even in the high school curriculum in my province anymore and I think that is unacceptable, nevermind just coming back to it later. <_<)
I've used imaginary numbers so much in my spare time, I don't even remember if the curriculum in England teaches it or not XD.

I have a question. I don't know how to do integrals yet, but I've seen that it can be used to find the volume of a sphere. Can this be done to find the area of a regular shape (something simple, like a triangle or a square) and more specifically, can it be used to find the area of a trapezium?

Spinor
February 9th, 2011, 07:33 PM
Even with AK47's explaination I still don't get how Mathematics is taught in the US. Etymologically, Precalculus means everything before Calculus, which would include 1st-grade education, like addition of single-digit numbers. Yet apparently people have somehow limited it to something between Algebra and Calculus, but adding the split of Algebra to Algebra I and Algebra II just confuses me even more.

Don't think of Pre-Calculus as a branch of mathematics or the set of all math down to first grade math before calculus >__> Algebra is split into Algebra I and II mostly because high school algebra is a deep subject and does require two years of proper study. Algebra II is also pretty expanded from the concepts of Algebra I, which was much more introductory to get the algebraic thinking straight.

And Pre-calculus should be thought of as a superset to Algebra II. First semester it's just accelerated Algebra II with preparation for skills in calculus. Second semester gets more abstract and gives advanced trigonometry and other subjects like polar coordinates in preparation for common topics in Calculus. Obviously, trig is abused in calculus like a doll under a dog o_o And other skills are also learned to apply calculus in other ways later on.

Username: ShinyMeowth
Overall Education Level: 9th grade
Mathematics Education Level: No idea what course this would apply to, since I've been studying at home, but I have studied Calculus up to triple integration, in Cartesian, Cylindrical and Spherical coordinates, and am currently studying Probability.
Do you think you can be asked for help in your level or lower?: Sure, always glad to help.
I wish I were a _______ so I could lay tangent to your curves: Derivative.

Woah woah what?! XD You're kidding right?! Multivariable Calculus in the ninth grade?! Are you Asian? I think I'd understand if you're homeschooled and you've been emphasized mathematics. I'll say, I'm impressed.

Anyway, Now that I have finished watching every Pokemon episode aired so far, 6 hours per day have been freed in my life. I plan to use these hours to study more, and I am planning to study, and finish number theory and group theory before I get to the 10th grade.
Slow down, you're making me feel bad o__o
Anyway, I would like to bring up a topic of conversation, what do you think of teachers teaching us incorrect rules that are to be removed or disproved later on? I personally have told my teacher off many times, but still she insists that negative numbers have no square root. My opinion is the same opinion I have about reproduction. Teachers should tell their students the truth, while leaving out unnecessary details. Teaching them something that is incorrect and even insisting on it when somebody refuses to take it? That is terrible teaching in my opinion.
Giving the wrong information is bad. If you do wonder and ask, teachers should be obligated to explain a little bit. At the very least send you to the library to do your own research. The dilemma of the square root of a negative number wasn't introduced to me until later in Algebra. I did my own researching to clear the question, and I had to wait until second semester of Algebra II to be introduced to i. >__>

Then again, I also still remember my 3rd grade teacher saying a number can't be subtracted something larger than itself >__> They're called negative numbers, people. I swear, I was bored in elementary school all the time.



Such interesting stuff I'm noticing, that more and more people seem to be advanced in their math studies, yet there's also many that are just normal or behind. I do wonder if legislatures for education should consider 'raising the bar'. Maybe the standard should be that advanced math studies should begin in 7th grade. It doesn't require too much compression of pre-algebraic mathematics, since it's a simple 10 year to 8 year compression. And I am confident that people should be perfectly capable of understanding advanced mathematics at a young age. So let Algebra and Geometry be things of 7th and 8th grade, and we have ourselves Advanced Algebra, Pre-calculus/Trigonometry, Calculus I, and Calculus II before college. Would it be a good idea to have that be the norm?

Cherrim
February 9th, 2011, 08:18 PM
My province outright lowered the bar. :/ Lots of idiots in standard schooling here.

(A lot of forum users are computer nerds who are more likely to be interested in math so you're gonna get a biased sample in this club. :P)

ShinyMeowth
February 10th, 2011, 04:57 AM
Don't think of Pre-Calculus as a branch of mathematics or the set of all math down to first grade math before calculus >__> Algebra is split into Algebra I and II mostly because high school algebra is a deep subject and does require two years of proper study. Algebra II is also pretty expanded from the concepts of Algebra I, which was much more introductory to get the algebraic thinking straight.

And Pre-calculus should be thought of as a superset to Algebra II. First semester it's just accelerated Algebra II with preparation for skills in calculus. Second semester gets more abstract and gives advanced trigonometry and other subjects like polar coordinates in preparation for common topics in Calculus. Obviously, trig is abused in calculus like a doll under a dog o_o And other skills are also learned to apply calculus in other ways later on.

Yeah, I can see how most of that works now.

Woah woah what?! XD You're kidding right?! Multivariable Calculus in the ninth grade?! Are you Asian? I think I'd understand if you're homeschooled and you've been emphasized mathematics. I'll say, I'm impressed.
Slow down, you're making me feel bad o__o
I have Asperger's. As a result, I have more advanced Mathematics skills than normal, but that is balanced out by my terrible Literature grades. I would love to be homeschooled, but unfortunately the Greek educational system is terrible, and there is no such thing here.

Then again, I also still remember my 3rd grade teacher saying a number can't be subtracted something larger than itself >__> They're called negative numbers, people. I swear, I was bored in elementary school all the time.
Wow, they refused to acknowledge negative numbers? That is like a billion times more ridiculous than ignoring imaginary ones.

Such interesting stuff I'm noticing, that more and more people seem to be advanced in their math studies, yet there's also many that are just normal or behind. I do wonder if legislatures for education should consider 'raising the bar'. Maybe the standard should be that advanced math studies should begin in 7th grade. It doesn't require too much compression of pre-algebraic mathematics, since it's a simple 10 year to 8 year compression. And I am confident that people should be perfectly capable of understanding advanced mathematics at a young age. So let Algebra and Geometry be things of 7th and 8th grade, and we have ourselves Advanced Algebra, Pre-calculus/Trigonometry, Calculus I, and Calculus II before college. Would it be a good idea to have that be the norm?Actually, I completely disagree with that. Raising the bar, especially on obligatory lessons is bound to make people focused on other topics fall back and fail the grades. What should be done in my opinion, would be to allow students to unrestrictedly skip grades (No idea if that's done in the US already, but it certainly is not here), allow homeschooling globally, and finally, let people choose lesson paths before the 4th grade, and allow them to switch later on, effectively limiting the hours spent at school, without doing any harm to the amount of knowledge people actually get. I mean, seriously, I calculated that I've wasted about 8,500 hours in that dump since the first grade. And I've been taught what I could study myself in about 100 hours. Talk about a waste of time. Another thing that I believe could work, would be to completely scrap off the first 5 grades, and push everything you are taught in these to the 6th. You don't learn much there anyway, and most of what you do will be contradicted later on. I never paid any attention at elementary school, and I had no problem functioning in the 7th grade at all.

Pokemon Trainer Touko
February 10th, 2011, 05:15 AM
Username: Pokemon Trainer Touko
Overall Education Level: Year 8
Mathematics Education Level: I study in Hong Kong so we have a different system. I might be the youngest here but I can beat year elevens :3 I've tried multivariate calculus and it wasn't that hard =]
Do you think you can be asked for help in your level or lower?: I guess so :D
I wish I were a _______ so I could lay tangent to your curves: Derivative

Please don't smash me with super hard stuff- I'm only 12 ~~

ShinyMeowth
February 10th, 2011, 10:50 AM
=:3 I've tried multivariate calculus and it wasn't that hard =]
I'm only 12 ~~
And now I can't boast at my school without feeling horrible anymore :P. Anyway, in the words of AK47, I'm impressed. Welcome to the Mathematics club, hope enjoy your stay :D

I like Pokemon (...)
February 10th, 2011, 01:42 PM
Woah woah what?! XD You're kidding right?! Multivariable Calculus in the ninth grade?! Are you Asian? I think I'd understand if you're homeschooled and you've been emphasized mathematics. I'll say, I'm impressed.
Slow down, you're making me feel bad o__o
The beautiful and dreadful thing about maths is that as long as you have a logical mind, EVERYTHING in math can be made easy. Honestly. The reason why you have those child prodigies who can do Uni level maths at the age of 5 is because they have a logical mind, and their parents allowed them to do that.
I know for certain that everyone in this club, if they had been given the opportunity, would be like the prodigies I mentioned. That's the beauty of maths; if I want to, I can learn anything I want as early as I want, unless it develops on some other branches (like calculus and trig).
The "dreadful" bit is that some ARE allowed to do higher level work much earlier than others who could, but aren't allowed. Take the example of ShinyMeowth and Pokemon Trainer Touko, they were allowed to do calculus and such at a young age, and we're feeling bad XD

Such interesting stuff I'm noticing, that more and more people seem to be advanced in their math studies, yet there's also many that are just normal or behind. I do wonder if legislatures for education should consider 'raising the bar'. Maybe the standard should be that advanced math studies should begin in 7th grade. It doesn't require too much compression of pre-algebraic mathematics, since it's a simple 10 year to 8 year compression. And I am confident that people should be perfectly capable of understanding advanced mathematics at a young age. So let Algebra and Geometry be things of 7th and 8th grade, and we have ourselves Advanced Algebra, Pre-calculus/Trigonometry, Calculus I, and Calculus II before college. Would it be a good idea to have that be the norm?
Here's the thing.
Obviously, mathematics and literacy are INCREDIBLY important for getting jobs, correct? If you can't read/write or do arithmetic, then, well, you're screwed.
But when you reach the age of, say, 14-15 at school, what you learn isn't really all that important for the average worker. Why do I need to learn to analyse a book, or learn quadratics? I don't.
I think that all the really important things should really be pushed until Year 9 (which is the final year, in England, that all subjects are compulsory). After that, it should really be optional. Of course, others would disagree.
I might be the youngest here but I can beat year elevens :3 I've tried multivariate calculus and it wasn't that hard =]
Please don't smash me with super hard stuff- I'm only 12 ~~
Mhm, like mentioned before, as long as you have someone that can explain every step and a logical mind, stuff like this can be taught to 12 year olds Unless you're going to tell me you learnt it when you were 8?

Otherworld9)
February 10th, 2011, 02:04 PM
(No idea if that's done in the US already, but it certainly is not here)

Being in Florida, my school is going to start doing that due to too many students getting a very low education and low skills in both math and literature. It hasn't started yet, but the principal did announce that if it were to happen(I only know it will happen in my middle school), yet he also mentioned it might not happen due to the economy. If it were though, 6th graders could skip to 7th and so on....as of skipping by will, I don't know much of that stuff, I'm still in research and barely turned 14 years old.

NurseBarbra
February 10th, 2011, 02:07 PM
Joining~
Username: Nurse Barbra
Overall Education Level: 3rd year (9th grade in american terms)
Mathematics Education Level:I do the new irish project maths sylubus, more wordy and complex equations, its about the equalivent of 12th grade maths,I know alot of the equations such as the distance between 2 points [^1/2{(a1+a1)^2+(b1+b2)^2}] ,
Do you think you can be asked for help in your level or lower?: Sure
I wish I were a _______ so I could lay tangent to your curves: n Angle of 35* or more~

Otherworld9)
February 10th, 2011, 05:27 PM
Joining~
Username: Nurse Barbra
Overall Education Level: 3rd year (9th grade in american terms)
Mathematics Education Level:I do the new irish project maths sylubus, more wordy and complex equations, its about the equalivent of 12th grade maths,I know alot of the equations such as the distance between 2 points [^1/2{(a1+a1)^2+(b1+b2)^2}] ,
Do you think you can be asked for help in your level or lower?: Sure
I wish I were a _______ so I could lay tangent to your curves: n Angle of 35* or more~


Welcome and hope you enjoy...wait for the leader to put you in the member list, I'm sure she would.

Spinor
February 17th, 2011, 06:32 PM
I am not impressed with the lack of productivity in the recent week.

Now to talk about why exactly you like math, or what you like about it and when did it get you so interested? Is there anything specific that had you hooked?

smile!
February 18th, 2011, 03:00 AM
I am not impressed with the lack of productivity in the recent week.

Now to talk about why exactly you like math, or what you like about it and when did it get you so interested? Is there anything specific that had you hooked?

Probably because we had no topic/no activity. Maybe we should set something like, a topic per week, or a random fact per, say, 5 days, or a quiz, or simply what you learn that week, or something like that.

Why exactly I like math? I don't really know why. It's just... fun, I guess. Like my lecturer said once, "When you get to prove the trigonometric equations, it felt fun, isn't it? Just like orgasm." The best part is when you get an answer to a question that's been bugging you for days.

Anything specific... I know someone is going to answer pi

Speaking of that, I'd really to learn more about the history behind constants like pi, e, etc. But the syllabus is just more centered around "How do you apply this to this" etc.

Anywayy.. Today entered the chapter derivative in graphing and application. The concavity part is still easy, but I have a feeling that the graph-sketching part is not going to be that simple.

Ninja Caterpie
February 18th, 2011, 03:08 AM
yeaaahh mathssss.

Username: Ninja Caterpie; NC, En-say
Overall Education Level: Year 9
Mathematics Education Level (Or most recent/advanced math subject): eh idg this.
Do you think you can be asked for help in your level or lower? Yes. Possibly a bit higher, too.
Life = The Universe = Everything = 42/3 = 14.

Pokemon Trainer Touko
February 18th, 2011, 03:23 AM
Now to talk about why exactly you like math, or what you like about it and when did it get you so interested? Is there anything specific that had you hooked?

I like maths because I get to go home at math lessons~ The teacher said that I don't need to attend until I get the same grade as the rest of the class~ :3

Impo
February 18th, 2011, 03:33 AM
...well, I like maths,

but right now in year 9 I am having some trouble with motion problems.
can anyone help with this?

I don't want to put the question because I want to try learn it myself, but does anyone know what I mean by motion problems?

smile!
February 18th, 2011, 04:48 AM
...well, I like maths,

but right now in year 9 I am having some trouble with motion problems.
can anyone help with this?

I don't want to put the question because I want to try learn it myself, but does anyone know what I mean by motion problems?

I can't imagine it. Maybe you can post the question, then we can give hints on how to solve it? Or try finding a similar question, maybe?

Impo
February 18th, 2011, 04:58 AM
okay, here's an example;

A motor cyclist makes a trip of 500km. If he had increased his speed by 10km/h, he could have covered 600km in the same time. What was his original speed?

smile!
February 18th, 2011, 05:43 AM
okay, here's an example;

A motor cyclist makes a trip of 500km. If he had increased his speed by 10km/h, he could have covered 600km in the same time. What was his original speed?

Some other members might have a different solution, but this would be what I did.

Hint:
We know that the basic equation is S=D/T.

We want to find S. D is already given. T is unknown. You cannot assign any value to T because T is fixed. So we have 2 unknowns. Therefore; use simultaneous equation.

Answer:
Equation 1... S=500/T
Equation 2... S+10=600/T (S+10 is because he increases the original S by 10)

So you get
1... TS = 500
2... T(S+10) = 600
..... TS + 10T = 600

Then substitute (1) into (2)
500 + 10T = 600

Solve for T, we get 10T = 100
Hence T = 10

Now that we know the value of T, we can continue solving for S
1... TS = 500
10S = 500
S = 50 km/h

Voila! :)

To recheck, you can try calculating the value of D.

Original speed = 50km/h, T = 10h, so D = 500 km
If speed is increased by 10 = 60 km/h, T = 10h, so D = 600 km

ShinyMeowth
February 18th, 2011, 06:14 AM
Now to talk about why exactly you like math, or what you like about it and when did it get you so interested? Is there anything specific that had you hooked?
Mathematics is a beautiful language. There is harmony, and everything follows a logical sequence. It is its perfection that made me fall in love with Math.
I like maths because I get to go home at math lessons~ The teacher said that I don't need to attend until I get the same grade as the rest of the class~ :3
You get to go home at math lessons? Wow, I really hate the educational system here. Instead of being able to do that, I am subjected to staying there and listen to the teacher rumble about things I already know (or in many cases, that are incorrect). However, I had a brilliant idea yesterday, that completely solved the problem of boring lessons for me. Before going to school, I print out about 10 sudokus, and solve them at the class. It makes time pass much faster, and requires actual thought.
okay, here's an example;

A motor cyclist makes a trip of 500km. If he had increased his speed by 10km/h, he could have covered 600km in the same time. What was his original speed?
In order to solve a problem using mathematics, you have to understand what each part of it means. Here, we want to find his original speed, "x". If we assume a constant amount of time, "n", we have "x*n=500km", since distance equals time * speed. The increased speed is x+10, so (x+10)*n=600. By solving both equations for n, we get n=500/x, and n=600/(x+10). We then merge these to 500/x=600/(x+10), and solve that:
500/x=600/(x+10)
(5000+500x)/(x^2+10x)=600x/(x^2+10x) (making the denominators equal)
5000+500x=600x (multiplying both sides with x^2+10x)
-100x=-5000
100x=5000
x=50km/h
If you have trouble with any part of that explanation, don't hesitate to ask for more details. What those problems need to be solved, is for you to write them down as an equation, and solving them becomes trivial after that.

Edit: Bah, ninja'd.

I like Pokemon (...)
February 18th, 2011, 09:58 AM
I am not impressed with the lack of productivity in the recent week.

Now to talk about why exactly you like math, or what you like about it and when did it get you so interested? Is there anything specific that had you hooked?
And then suddenly, the club comes to life.

Why I like maths? That's... quite a hard question to answer, but I'll give it a go and probably write about e^3 pages worth of text.

I felt the need to spoiler it:
I've always been quite good at subjects like maths and science. Whether that was because I have a logical mind, or because I hit my head when I was small, I don't know.

I like how maths can be both abstract and practical at the same time. You can learn about geometry and topology, and apply it, or you can learn about number theory, and just marvel at how pieces fall together like a jigsaw.

There's also the challenging side, where I'll see a difficult question and try to solve it. I find that I enjoy it more when there are more steps to work out, and that I won't know what to do for a bit, but eventually I get a "Eureka!" moment.

There's also the pure beauty of mathematics itself. How numbers can just... fall into place. How the fibonacci numbers, when put into a fraction, solve the equation: a/b = (b+a)/a. And how when you flip the fraction, you get a number that is 1 less than your first number, AND its reciprocal. I just got a Eureka moment from that.

I find as well, though, that I like how equations have a very limitted number of answers. 1 + 1 will ALWAYS equal 2. Always, always, always except for binary and unary. That's something that I don't like about English, where any answer can be made valid. In maths, everything is black and white. It either is or it isn't. At least, that's how I feel about it.

And finally, my friends are sick of me saying this, but maths is the basis of everything. "All living things are biology and all non-living things are chemistry or physics. Biology is all chemical reactions. Chemistry is all reactions of particles. Physics is just maths."

Impo
February 18th, 2011, 05:17 PM
thanks for the help, smile and shinymeowth :)

i think i get it now :)

NurseBarbra
February 18th, 2011, 06:04 PM
Behold some questions from todays test for me, i got all the right answers but im just gonna throw it out there for you all. (As Quoted directly from the test):

1) Algebra
a) Given that:
x+2y= p
3

Express y in terms of x and p

b)i) Solve x^2 -13x-36 = 0
b)ii) Hence find the two values of t ∈R for which

((1/t + 2)^2] -13(1/t + 2) + 36 = 0

c) The length of one side of a rectangle is x+4, The area is x^2+16x+48
i) Find the expression of x as the length of the other side.

D)

_1_ + _1_
x+1 . x-1

i) Express in its simplisted form.
ii) Hence if the equation equals 3, Express your answer in the form of A+B√10 Where A,B ∈Q.



...Have fun~

smile!
February 18th, 2011, 06:15 PM
Edit: Bah, ninja'd.

:P



There's also the pure beauty of mathematics itself. How numbers can just... fall into place. How the fibonacci numbers, when put into a fraction, solve the equation: a/b = (b+a)/a. And how when you flip the fraction, you get a number that is 1 less than your first number, AND its reciprocal. I just got a Eureka moment from that.

Eh...? Explain. :P


I find as well, though, that I like how equations have a very limitted number of answers. 1 + 1 will ALWAYS equal 2.

Didn't you get that 1+1=4 once? XD


And finally, my friends are sick of me saying this, but maths is the basis of everything. "All living things are biology and all non-living things are chemistry or physics. Biology is all chemical reactions. Chemistry is all reactions of particles. Physics is just maths."

The quote kinda contradicts what you're saying....

thanks for the help, smile and shinymeowth :)

i think i get it now :)

Glad to be of help =]

Spinor
February 18th, 2011, 11:41 PM
1) Algebra
a) Given that:
x+2y= p
3

Express y in terms of x and p
(x+2y)/3=p

*3

x+2y = 3p

-x

2y = 3p - x

/2

y = (3p - x)/2
b)i) Solve x^2 -13x-36 = 0
(13) +- sqrt(169- 4*1*-36)
all over 2

(13 (+-) sqrt(313)) / 2

b)ii) Hence find the two values of t ∈R for which

((1/t + 2)^2] -13(1/t + 2) + 36 = 0

(-3 (+-) sqrt(6))/6

c) The length of one side of a rectangle is x+4, The area is x^2+16x+48
i) Find the expression of x as the length of the other side.

x+12

D)

_1_ + _1_
x+1 . x-1

i) Express in its simplisted form.
(2x)/(x^2-1)
ii) Hence if the equation equals 3, Express your answer in the form of A+B√10 Where A,B ∈Q.

I keep getting non-rational answers >__> (-sqrt(2)+sqrt(10))/(2*sqrt(2))

ShinyMeowth
February 19th, 2011, 06:03 AM
(2x)/(x^2-1)
ii) Hence if the equation equals 3, Express your answer in the form of A+B√10 Where A,B ∈Q.

I keep getting non-rational answers >__> (-sqrt(2)+sqrt(10))/(2*sqrt(2))

(2x)/(x^2-1)=3
2x=3(x^2-1)
2x=3x^2-3
-3x^2+2x+3=0
x=(-2±√(4+36))/-6
x=(-2±√40)-6
x=(-2±(√4*√10))/-6
x=(-2±2√10)/-6
x=(-1±√10)/-3
x=1/3 ±√10/3
A=1/3, B=1/3

Spinor
February 19th, 2011, 08:51 AM
(2x)/(x^2-1)=3
2x=3(x^2-1)
2x=3x^2-3
-3x^2+2x+3=0
x=(-2±√(4+36))/-6
x=(-2±√40)-6
x=(-2±(√4*√10))/-6
x=(-2±2√10)/-6
x=(-1±√10)/-3
x=1/3 ±√10/3
A=1/3, B=1/3


It was a good attempt if you consider it was 2 AM when I did this... >__>

ShinyMeowth
February 19th, 2011, 09:17 AM
It was a good attempt if you consider it was 2 AM when I did this... >__>
Which reminds me of an incredibly stupid mistake I made on a math test, due to thinking of Pokemon the whole time. I had finished the whole excersize, and had to evaluate 2*5^2. So I went on and automatically wrote 2*5^2=2*20=40, and gave the paper to the teacher, only to realize what I had done when the bell dismissed us, but then it was too late.

NurseBarbra
February 19th, 2011, 07:34 PM
Behold some questions from todays test for me, i got all the right answers but im just gonna throw it out there for you all. (As Quoted directly from the test):

1) Algebra
a) Given that:
x+2y= p
3

Express y in terms of x and p

b)i) Solve x^2 -13x-36 = 0
b)ii) Hence find the two values of t ∈R for which

((1/t + 2)^2] -13(1/t + 2) + 36 = 0

c) The length of one side of a rectangle is x+4, The area is x^2+16x+48
i) Find the expression of x as the length of the other side.

D)

_1_ + _1_
x+1 . x-1

i) Express in its simplisted form.
ii) Hence if the equation equals 3, Express your answer in the form of A+B√10 Where A,B ∈Q.



...Have fun~

I actually made a mistake when i typed in this.
b)i) is actually "x^2 -13x+36 = 0"
Answer time:

a) (3p-x)/2 = y
b)i) (x-4)(x-9)= 0
∴ x-4=0 , x-9=0
∴ x=4 ,x=9
b)ii) 1/t -2 = 4 , 9
∴ 1-2t = 4t, 9t
∴ 1 = 6t, 11t
∴ t = 1/6 , 1/11
c) x+12
d)i)
_1_ + _1_
x+1 . x-1
∴x+1+x-1
. (x^2)-1
∴__2x__
. [x^2]-1
ii)2x/[x^2]-1 = 3
(answer in the form "a+b(sqrt10)", equation: [Ax^2 + Bx + C])
∴ 2x = 3(x^2-1)
∴ 2x = 3x^2 -3
∴ 3x^2 -2x-3 = 0
∴ 3+2(sqrt10)

correct answers are in BOLD
yay for the irish maths system~

Edit: Note: These were 4 SEPERATE questions. In our maths system the "1) Algebra" is the section " a) " is the question , ergo : question A. and "i" is used for the seperate parts of the question.

ShinyMeowth
February 20th, 2011, 03:53 AM
ii)2x/[x^2]-1 = 3
(answer in the form "a+b(sqrt10)", equation: [Ax^2 + Bx + C])
∴ 2x = 3(x^2-1)
∴ 2x = 3x^2 -3
∴ 3x^2 -2x-3 = 0
∴ 3+2(sqrt10)


The part where you solve the quadratic equation is mistaken. Everything up to that is correct. The quadratic formula is x=(-b+√(b²-4ac))/2a.
a=3, b=-2, c=-3.
By substituting the values,
x=(-(-2)+√((-2)²-4*3*(-3))/(2*3)
x=(2+√(4+36))/6
x=(2+√40)/6
x=(2+√10√4)/6
x=(2+2√10)/6
x=(1+√10)/3
x=1/3+√10)/3
But from what I have seen, that was probably done due to a "5²=20"-type mistake.

I like Pokemon (...)
February 20th, 2011, 05:05 AM
Eh...? Explain. :P
x-1 = 1/x
and
y+1 = 1/y
When x = (√5 +1)/2
and when y = (√5 -1)/2

And when you get the fibonacci sequence (1, 1, 2, 3, 5, 8, 13, 21, etc. where you take the previous number and add it to the last number to get the next number) and put it as a fraction (1/1, 1/2, 2/3, 3/5, 5/8, 8/13, etc.) the fraction converges to (√5-1)/2. When you flip the fraction (1/1, 2/1, 3/2, 5/3, 8/5, 13/8, etc.) the fraction converges to (√5 +1)/2. Which is also the golden ratio, which is supposed to be related to beauty or something like that.

The quote kinda contradicts what you're saying....
How so?

I swear I'd have given that stuff a try if I came to the club earlier.

MeerFall
February 20th, 2011, 05:38 AM
who like algabra?! (puts hand up)

NurseBarbra
February 20th, 2011, 08:19 AM
The part where you solve the quadratic equation is mistaken. Everything up to that is correct. The quadratic formula is x=(-b+√(b²-4ac))/2a.
a=3, b=-2, c=-3.
By substituting the values,
x=(-(-2)+√((-2)²-4*3*(-3))/(2*3)
x=(2+√(4+36))/6
x=(2+√40)/6
x=(2+√10√4)/6
x=(2+2√10)/6
x=(1+√10)/3
x=1/3+√10)/3
But from what I have seen, that was probably done due to a "5²=20"-type mistake.

sorry, i looked at the wrong equation, the next question was the equation of a line and the formulas are on top of eachother. (Fail on my regard)

ShinyMeowth
February 20th, 2011, 08:20 AM
sorry, i looked at the wrong equation, the next question was the equation of a line and the formulas are on top of eachother. (Fail on my regard)
Don't worry about it, as long as you don't do it on a test.

NurseBarbra
February 20th, 2011, 04:00 PM
Well the formulas arent labeled and there like this in order of the questions(the test was 40 questions long):
-b+-√(b²-4(a)(c))
2a
ax²+bx+c
(x+h)² = (x+xh+h)
4/3πr³

Spinor
February 20th, 2011, 04:55 PM
who like algabra?! (puts hand up)

I'm too busy dealing with Manly stuff like Analysis and Topology to deal with Algebra ^____^

smile!
February 21st, 2011, 02:22 AM
x-1 = 1/x
and
y+1 = 1/y
When x = (√5 +1)/2
and when y = (√5 -1)/2

And when you get the fibonacci sequence (1, 1, 2, 3, 5, 8, 13, 21, etc. where you take the previous number and add it to the last number to get the next number) and put it as a fraction (1/1, 1/2, 2/3, 3/5, 5/8, 8/13, etc.) the fraction converges to (√5-1)/2. When you flip the fraction (1/1, 2/1, 3/2, 5/3, 8/5, 13/8, etc.) the fraction converges to (√5 +1)/2. Which is also the golden ratio, which is supposed to be related to beauty or something like that.


How so?

I swear I'd have given that stuff a try if I came to the club earlier.

...I'll get back to you on that during a convo. XD

How so? Err.. The way I understood your sentence is that Maths = everything but then you limited to physics is just maths. What about Biology and Chemistry?

Regeneration
February 21st, 2011, 02:26 AM
Well the formulas arent labeled and there like this in order of the questions(the test was 40 questions long):
-b+-√(b²-4(a)(c))
2a
ax²+bx+c
(x+h)² = (x+xh+h)
4/3πr³
-b+-√(b²-4(a)(c)) - Quadratic formula
2a

ax²+bx+c - General form of a linear equation in 2 variables.

(x+h)² = (x+xh+h) - Aren't x and h supposed to be squared and isn't xh supposed to be 2xh? o.o

4/3πr³ - Volume of a sphere

I like Pokemon (...)
February 21st, 2011, 10:25 AM
How so? Err.. The way I understood your sentence is that Maths = everything but then you limited to physics is just maths. What about Biology and Chemistry?
I guess I didn't make it clear, that Biology was just Chemistry, and Chemistry was just Physics


And on my test papers, I have all of those as well as:
Volume of a pyramid/cone: [base]*[perpendicular height]/3
Volume of a prism: [Area of cross section]*[length]
Area of a trapezium: h(a+b)/2

NurseBarbra
February 22nd, 2011, 12:36 PM
(x+h)² = (x+xh+h) - Aren't x and h supposed to be squared and isn't xh supposed to be 2xh? o.o

Yeah but my teacher is kinda derp when it comes to equations. can't actually believe that he became a maths teacher. in class he put down 5(10)=510 one time.

Impo
February 23rd, 2011, 02:10 AM
Yeah but my teacher is kinda derp when it comes to equations. can't actually believe that he became a maths teacher. in class he put down 5(10)=510 one time.

..i think you should take his place.

and my teacher decided to give the class a directed investigation, and he's giving us a whole week. the questions are really hard (for me, anyway), and i've only managed to solve 3 out of 5 the first day. i wanna see how people here fair, i'm expecting for all of you to get it in like 5 seconds and make me feel stupid :P , but here they are;

A girl thinks of 3 numbers. She adds these numbers in pairs, getting 11, 17 and 22.
What are the three numbers?
(This took me so long to get, it was like a sudden brain wave and i got the answer. i then spiraled into a 10 minute victory dance with my friend, because we conquered the maths)

The sum of two numbers is 8 and the difference between their squares is 34.
Find their difference.
(This one annoyed me alot, took me a while to realise the seemingly obvious, but i got it)

and the other ones a calendar one that i can't be bothered typing.
as soon as i finish the others im going to post them and see if others can solve them too :)

Pokemon Trainer Touko
February 23rd, 2011, 02:20 AM
Oh my god~! My classmates are doing trigonometry and they don't even know what's the sine and cosine rules~?!?! :O Unbelievable~!

smile!
February 23rd, 2011, 02:46 AM
I guess I didn't make it clear, that Biology was just Chemistry, and Chemistry was just Physics


Oh, okay. XD


A girl thinks of 3 numbers. She adds these numbers in pairs, getting 11, 17 and 22.
What are the three numbers?

The sum of two numbers is 8 and the difference between their squares is 34.
Find their difference.

I miss doing these kinds of questions. XD

Basically, it's how you manipulate the algebra. For the first one, just assign the numbers as x, y and z. Then make an equation for each and solve them accordingly.

For the second, it's about factorization. As long as you know that x2 - y2 = (x+y)(x-y), you should be able to do it.

Impo
February 23rd, 2011, 02:56 AM
Oh, okay. XD



I miss doing these kinds of questions. XD

Basically, it's how you manipulate the algebra. For the first one, just assign the numbers as x, y and z. Then make an equation for each and solve them accordingly.

For the second, it's about factorization. As long as you know that x2 - y2 = (x+y)(x-y), you should be able to do it.

hehe, i've done them already. it took me a while, i forgot about difference of two squares for a while. i wanted to see how fast you could do it, and im guessing it took two seconds.

how are you so good at maths? i'm so jealous.

Dude22376
February 23rd, 2011, 03:36 AM
Uh, those questions aren't really that hard, unless you don't know algebra.

1) Let the numbers be x, y and z.
x + y = 11 (1)
x + z = 17 (2)
y + z = 22 (3)
As there are 3 unknowns and 3 equations we should be able to solve it.
(1) + (3): x + 2y + z = 33
Subtract (2): 2y = 16 thus y = 8
The rest is just basic manipulation, x = 3 and z = 14.

2) Let the numbers be x and y, x > y.
x + y = 8 (1)
x^2 - y^2 = 34 (2)
Again we have 2 equations and 2 unknowns, so it should be solvable.
Rearranging (1): y = 8 - x
Substituting into (2): x^2 - (8 - x)^2 = 34
Expanding: x^2 - 64 + 16x - x^2 = 34
Cancelling x squared and shifting -64 over: 16x = 34 + 64, thus x = 6.125
Then y = 1.875

If you want to get past your mental block at doing maths, just remember that if there are n equations and n unknowns, you should be able to solve for every unknown. Write down equations representing everything that is given to you in the question. Then solve those equations for the answers.
At your level, only substitution and elimination are needed. My answers for the two questions you provided display both techniques (eliminating x + z in the first and substituting 8 - x in the second).
If there are more unknowns than there are equations, then the question can't be solved!
If there are 2 equations which mean the same thing (like x + y = 3 and 2x + 2y = 6), then you can totally ignore one of those equations. If this puts you in a situation where there are more unknowns than equations, then the question can't be solved.

Oh, and if you want your equations to be displayed nicely on forums, try using Texify. It'll take some time to learn how to use, but you'll be able to display superscripts, subscripts, Greek letters, differential/integral signs, etc. Sadly I can't use it because I don't have 15 posts yet :(

Impo
February 23rd, 2011, 04:29 AM
ahhh, imma try all the harder ones now :) ,

Regeneration
February 23rd, 2011, 04:46 AM
This thread needs more manly trigonometry questions. I have one if anybody is bored:
If sinθ + cosθ = √2cos(90° - θ), find cot θ.

It's not really difficult, anyone wants to try?

Dude22376
February 23rd, 2011, 05:06 AM
Let theta=x, it's easier than entering Greek characters.
cos(90-x) is sin x, substitute that in:
sin x + cos x = sqrt(2) sin x
Divide by sin x on both sides (assuming sin x is not 0):
1 + cos x/sin x = sqrt(2)
cos x/sin x is cot x, which is sqrt(2) - 1.

Regeneration
February 23rd, 2011, 05:36 AM
Let theta=x, it's easier than entering Greek characters.
cos(90-x) is sin x, substitute that in:
sin x + cos x = sqrt(2) sin x
Divide by sin x on both sides (assuming sin x is not 0):
1 + cos x/sin x = sqrt(2)
cos x/sin x is cot x, which is sqrt(2) - 1.
Nice, that is the correct answer. I need to think of tougher questions now! >:D

My final examinations are fast approaching, so gotta practise lots of math. XD

NurseBarbra
February 23rd, 2011, 11:15 AM
Oh my god~! My classmates are doing trigonometry and they don't even know what's the sine and cosine rules~?!?! :O Unbelievable~!
Seriousally? well heres an easy way to remember Sin,Cos,Tan
Sin: Oh hell (O/H)
Cos: Another Hour (A/H)
Tan: Of Algebra (O/A)

ShinyMeowth
February 23rd, 2011, 11:54 AM
Seriousally? well heres an easy way to remember Sin,Cos,Tan
Sin: Oh hell (O/H)
Cos: Another Hour (A/H)
Tan: Of Algebra (O/A)
Insulting as this may be, I find it amusing and useful. I approve of it.
Oh my god~! My classmates are doing trigonometry and they don't even know what's the sine and cosine rules~?!?! :O Unbelievable~!
Assuming you are talking about the laws of sines and cosines, and not just the definitions of the functions, I have not memorized them either. I try to avoid memorizing stuff as much as I can, since deriving them from the basics is much more rewarding. It is quite fun when my mathematician tells me to solve a trigonometry problem on the blackboard. I derive everything from the basics, which takes ages. My teacher has learned not to get me on the blackboard the hard way. That is not the case with constants, however, since I want to maximize accuracy whenever I can. I remember once when we had a problem involving circles, which brought in pi. The teacher made the foolish mistake to make me solve it, and I went and used "3,141592653589793238462643383279506884197169399375" instead of "3,14". She ended up stopping me, and making me return to my seat, when she saw me multiplying that by the square of some number.

Drekin
February 23rd, 2011, 11:58 AM
Username: Drekin
Overall Education Level: Highschool math plus 13 credit hours after this semester is over
Mathematics Education Level (Or most recent/advanced math subject): College Calculus I
Do you think you can be asked for help in your level or lower?: Definitely
Life = The Universe = Everything = : 42 (shouldn't it be Life + The Universe + Everything = ? )

Impo
February 23rd, 2011, 03:53 PM
Seriousally? well heres an easy way to remember Sin,Cos,Tan
Sin: Oh hell (O/H)
Cos: Another Hour (A/H)
Tan: Of Algebra (O/A)

it took me a full day to realize what that meant.

here's my way of remembering;

S.O.H.C.A.H.T.O.A.

..you all know what the letters represent

smile!
February 26th, 2011, 04:34 AM
2) Let the numbers be x and y, x > y.
x + y = 8 (1)
x^2 - y^2 = 34 (2)
Again we have 2 equations and 2 unknowns, so it should be solvable.
Rearranging (1): y = 8 - x
Substituting into (2): x^2 - (8 - x)^2 = 34
Expanding: x^2 - 64 + 16x - x^2 = 34
Cancelling x squared and shifting -64 over: 16x = 34 + 64, thus x = 6.125
Then y = 1.875

Actually, that wouldn't be necessary. Well, Unless you want to find the true value of x and y. Because

x + y = 8 ... (1)
x2 - y2 = 34 ... Factorize
(x+y)(x-y) = 34

From ... (1)
8(x-y) = 34
x-y = 34/8

Since the question asked for the difference of x and y, there's no need to solve for x and y.

This thread needs more manly trigonometry questions. I have one if anybody is bored:
If sinθ + cosθ = √2cos(90° - θ), find cot θ.

It's not really difficult, anyone wants to try?

Gah. I hate Trigonometry. idk why. >.< Couldn't be bothered to remember all the values for cos/sin/tan pi/3, pi/6 etc.

Does someone has a formula for memorizing them? XD I know that you can basically just draw the unit circle and find the value, but I want to memorize them. It's way quicker to get, especially in exams.

Seriousally? well heres an easy way to remember Sin,Cos,Tan
Sin: Oh hell (O/H)
Cos: Another Hour (A/H)
Tan: Of Algebra (O/A)

XD That's awesome XP

I remember once when we had a problem involving circles, which brought in pi. The teacher made the foolish mistake to make me solve it, and I went and used "3,141592653589793238462643383279506884197169399375" instead of "3,14". She ended up stopping me, and making me return to my seat, when she saw me multiplying that by the square of some number.

WIN


how are you so good at maths? i'm so jealous.

It does help that I did those during my high school years, and I'm now in college studying things like derivatives and local linear approximations and whatnot XD

Regeneration
February 26th, 2011, 04:50 AM
Gah. I hate Trigonometry. idk why. >.< Couldn't be bothered to remember all the values for cos/sin/tan pi/3, pi/6 etc.

Does someone has a formula for memorizing them? XD I know that you can basically just draw the unit circle and find the value, but I want to memorize them. It's way quicker to get, especially in exams.

I have memorised the values of cos, sin, tan, etc. for 0, 30, 45, 60 and 90 degrees.

I learned only the values of Sin. (In degrees)
Sin 0 = 0 = Cos 90
Sin 30 = 1/2 = Cos 60
Sin 45 = 1 /√2 = Cos 45
Sin 60 = √3/2 = Cos 30
Sin 90 = 1 = Cos 0
If you noticed, the values of Cos are just opposite of those of Sin.

Then, Tan = Sin/ Cos
Cosec = 1/Sin
Sec = 1/Cos
Cot = 1/Tan = Cos/ Sin

That way, you can remember the values with the help of just memorising the values of just Sin. We get to use a log table for all other values. XD

Dude22376
February 26th, 2011, 05:34 AM
Yeah, that is a faster way of doing it. I guess it depends on whether you can spot such a shortcut right away or not.

I memorize all trigonometric values by imprinting a picture of their graphs in my mind (i.e. y = sin x, y = cos x, y = tan x). So I know right away that, for example, sin x starts at 0, goes up to 1, back down to 0, then -1, then 0 again.

One more thing when converting between radians and degrees: pi/6 is 30 and pi/3 is 60.

smile!
February 26th, 2011, 07:22 AM
I learned only the values of Sin. (In degrees)
Sin 0 = 0 = Cos 90
Sin 30 = 1/2 = Cos 60
Sin 45 = 1 /√2 = Cos 45
Sin 60 = √3/2 = Cos 30
Sin 90 = 1 = Cos 0
If you noticed, the values of Cos are just opposite of those of Sin.

Then, Tan = Sin/ Cos
Cosec = 1/Sin
Sec = 1/Cos
Cot = 1/Tan = Cos/ Sin

That way, you can remember the values with the help of just memorising the values of just Sin. We get to use a log table for all other values. XD


Ooh. I remember trying the same approach last year. XD But when we moved into Calculus this year, I have forgotten all those Precalc methods I've devised. XD THANKS!

Yeah, that is a faster way of doing it. I guess it depends on whether you can spot such a shortcut right away or not.

I memorize all trigonometric values by imprinting a picture of their graphs in my mind (i.e. y = sin x, y = cos x, y = tan x). So I know right away that, for example, sin x starts at 0, goes up to 1, back down to 0, then -1, then 0 again.

One more thing when converting between radians and degrees: pi/6 is 30 and pi/3 is 60.

Mhm. I used to get stumped on such questions as well. Like, this can't be factorized. Heck, how am I going to get the value? Then my friend showed me that method, and I realized that you don't really need the value. It's more of how creative you are.

Memorizing graph pattern, cool. That could help. Thanks :)

I like Pokemon (...)
February 26th, 2011, 07:23 AM
Assuming you are talking about the laws of sines and cosines, and not just the definitions of the functions, I have not memorized them either. I try to avoid memorizing stuff as much as I can, since deriving them from the basics is much more rewarding. It is quite fun when my mathematician tells me to solve a trigonometry problem on the blackboard. I derive everything from the basics, which takes ages. My teacher has learned not to get me on the blackboard the hard way. That is not the case with constants, however, since I want to maximize accuracy whenever I can. I remember once when we had a problem involving circles, which brought in pi. The teacher made the foolish mistake to make me solve it, and I went and used "3,141592653589793238462643383279506884197169399375" instead of "3,14". She ended up stopping me, and making me return to my seat, when she saw me multiplying that by the square of some number.
Wow, that's just awesome.
And I agree with you on deriving any formulae, mainly because I don't trust my brain to get ALL the numbers correct when memorising, plus it's fun, and as you said it feels rewarding, and I can trust that I've gotten it right at the end.
As for memorising constants, I would like to memorise up to about 6 decimals (an accuracy to a millionth) but I know that Pi is 3.1415926 (7 decimals), e begins with 2, and phi begins with 1.618.


I have memorised the values of cos, sin, tan, etc. for 0, 30, 45, 60 and 90 degrees.

I learned only the values of Sin. (In degrees)
Sin 0 = 0 = Cos 90
Sin 30 = 1/2 = Cos 60
Sin 45 = 1 /√2 = Cos 45
Sin 60 = √3/2 = Cos 30
Sin 90 = 1 = Cos 0
If you noticed, the values of Cos are just opposite of those of Sin.

Then, Tan = Sin/ Cos
Cosec = 1/Sin
Sec = 1/Cos
Cot = 1/Tan = Cos/ Sin
That's actually very useful, perhaps I'll try and memorise that. It's a shame that, in school, I've only done SohCahToa, Law of Sine and Law of Cosine. I haven't been taught how the rules are related to each other (like Cosine and Sine are "reversed" and Tan is Sin/Cos), or anything like that.

ShinyMeowth
February 26th, 2011, 07:24 AM
Sin 0 = 0 = Cos 90
Sin 30 = 1/2 = Cos 60
Sin 45 = 1 /√2 = Cos 45
Sin 60 = √3/2 = Cos 30
Sin 90 = 1 = Cos 0
If you noticed, the values of Cos are just opposite of those of Sin.

The observation is correct, but the opposite of x is -x. What you meant is sin(45°±a)=cos(45°∓a).

I never memorize trigonometric values, since those most commonly used ones can be easily found by constructing triangles, and whenever you need something like sin(17), you are definitely going to have access to a table anyway.

Dude22376
February 26th, 2011, 07:42 AM
I, on the other hand, always memorize formulas. I may have a go at deriving them when I have time, but I never derive formulas during tests/exams. Try deriving the ideal gas equation and tell me that memorizing PV = nRT is harder.
It actually isn't that hard, if you've done enough practice problems you can always fill in the correct numbers in the correct places. It's a bit like muscle memory.
Writing down every necessary formula on a piece of paper also helps.

I don't memorize constants like pi either - your answer is always either computed using a calculator, or given in terms of pi.

smile!
February 26th, 2011, 08:22 AM
I never memorize trigonometric values, since those most commonly used ones can be easily found by constructing triangles, and whenever you need something like sin(17), you are definitely going to have access to a table anyway.

Yeah, but constructing triangles take time, and time is essential in a test. >.< Or in class, when your lecturer asks something and wants the answer fast. That is why I prefer memorizing. But you have a point there. If you suddenly get blank in an exam, you can start from scratch if you understand the basics and know how to construct the table.

I, on the other hand, always memorize formulas. I may have a go at deriving them when I have time, but I never derive formulas during tests/exams.

Writing down every necessary formula on a piece of paper also helps.

I don't memorize constants like pi either - your answer is always either computed using a calculator, or given in terms of pi.

I concur. :P

THAT. I seriously need to do that. First Principles, Newton's Method, Rolle's Theorem, Local Linear Approximation... They're all scattered throughout my notes. XD

We used to substitute pi for 22/7 or 3.142 in the high school, but now we give the answers in terms of pi instead. I love that better, because substituting pi for 22/7 or 3.142 doesn't really give a correct answer.


Also, I don't know whether you guys already know about this, but.
Speaking about pi, if you use 22/7 as pi, the equivalent value is 3.142857142857142857....

If you notice, we have a recurring sequence there, which is 142857. It's a roundabout number, i.e whenever you multiply that number by e.g 2, you get the same numbers, only in different sequence.

142857 x 2 = 285, 714
142857 x 3 = 428, 571
142857 x 4 = 571, 428
.
.
.
142857 x 7 = 999, 999
142857 x 8 = 1, 142, 856 (notice that 6+1 = 7 so essentially it's still 142, 857)

I don't know how far this number will stay the same though. XD

Regeneration
February 26th, 2011, 09:38 AM
Derive a formula during tests? No way. Unless that is what the question asks. XD

Memorising formulae is not difficult at all if you're practising maths a lot. You'll keep using them and hence easily memorise them all.

smile!
February 28th, 2011, 07:42 AM
If there's one thing I hate more than trigonometry, it's modulus, I swear. They drive me nuts on limit questions. x.x I wonder if someone can help me with this?

Determine whether all the hypotheses of the Mean-Value Theorem are satisfied on the stated interval. If they are not satisfied, find all values of c guaranteed in the conclusion of the theorem.

f(x) = |x-1| on [-2,2]

...I didn't even understand the last part of the question. o.o Anyone? :3

Dude22376
February 28th, 2011, 08:02 AM
The hypotheses required are:
(1) f(x) is continuous on [-2,2], and
(2) f(x) is differentiable on (-2,2)

The first statement is easy to prove: |x-1| can be piecewise defined, as 1-x if x < 1, 0 if x=1, and x-1 if x > 1. Since x-1 is a polynomial, and all polynomials are continuous over R, f(x) is continuous over [-2,1) and (1,2].
Next, we must check for continuity at x=1.
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E-%7Df%28x%29%20%3D%201-1%20%3D0.gif
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E%2B%7Df%28x%29%20%3D%201-1%20%3D0.gif
f(1) = 0
All 3 numbers match, so f(x) is continuous at x=1.

The second statement can be seen as false graphically: there is a corner point at x=1. However, we must prove this rigorously (no graphical methods are acceptable).

Start with the definition of derivative, calculate the left-hand derivative:
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7Bf%28x%29-f%281%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7Bf%28x%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7B1-x%7D%7Bx-1%7D%3D-1.gif
Noting that f(1) = 0, and using the piecewise definition of f(x) as described earlier.
Then calculate the right-hand derivative:
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bf%28x%29-f%281%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bf%28x%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bx-1%7D%7Bx-1%7D%3D1.gif
Since they are not the same, f(x) is not differentiable at x=1, so (2) is false.

One of the conditions was not satisfied, so no values of f'(c) are guaranteed. (1 - 3)/(2 - (-2)) = -0.5.
The only values of f' at the points where it is differentiable are 1 or -1.

p.s. I'm pretty sure the last part of the question is worded wrongly, because:
1) "not satisfied" = theorem doesn't count for anything
2) MVT involves f'(c), and does not state exactly which, or how many, values c could take.

smile!
February 28th, 2011, 08:32 AM
The hypotheses required are:
(1) f(x) is continuous on [-2,2], and
(2) f(x) is differentiable on (-2,2)

The first statement is easy to prove: |x-1| can be piecewise defined, as 1-x if x < 1, 0 if x=1, and x-1 if x > 1. Since x-1 is a polynomial, and all polynomials are continuous over R, f(x) is continuous over [-2,1) and (1,2].
Next, we must check for continuity at x=1.
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E-%7Df%28x%29%20%3D%201-1%20%3D0.gif
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E%2B%7Df%28x%29%20%3D%201-1%20%3D0.gif
f(1) = 0
All 3 numbers match, so f(x) is continuous at x=1.

The second statement can be seen as false graphically: there is a corner point at x=1. However, we must prove this rigorously (no graphical methods are acceptable).

Start with the definition of derivative, calculate the left-hand derivative:
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7Bf%28x%29-f%281%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7Bf%28x%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E-%7D%5Cfrac%7B1-x%7D%7Bx-1%7D%3D-1.gif
Noting that f(1) = 0, and using the piecewise definition of f(x) as described earlier.
Then calculate the right-hand derivative:
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bf%28x%29-f%281%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bf%28x%29%7D%7Bx-1%7D%3D%20%5Clim_%7Bx%5Cto1%5E%2B%7D%5Cfrac%7Bx-1%7D%7Bx-1%7D%3D1.gif
Since they are not the same, f(x) is not differentiable at x=1, so (2) is false.

One of the conditions was not satisfied, so no values of f'(c) are guaranteed. (1 - 3)/(2 - (-2)) = -0.5.
The only values of f' at the points where it is differentiable are 1 or -1.

p.s. I'm pretty sure the last part of the question is worded wrongly, because:
1) "not satisfied" = theorem doesn't count for anything
2) MVT involves f'(c), and does not state exactly which, or how many, values c could take.

Thank you! That was a great help ^^
And yeah, I don't know whether the last part of question is worded correctly. I'll ask my lecturer again to clarify. Anyway, thanks again! 8D

I didn't quite get that last part, though. The last 2 lines before the postnote.

Dude22376
February 28th, 2011, 08:45 AM
This should be clearer.

f(2) = 1
f(-2) = 3.
(f(2) - f(-2))/(2 - (-2)) = -0.5.

d/dx (x-1) = 1 and d/dx (1-x) = -1.

smile!
February 28th, 2011, 08:50 AM
This should be clearer.

f(2) = 1
f(-2) = 3.
(f(2) - f(-2))/(2 - (-2)) = -0.5.

d/dx (x-1) = 1 and d/dx (1-x) = -1.

Ah, of course. It's to clarify f(b)-f(a)/b-a = f'(c) right? I forgot the Theorem itself, lol. Thanks very much ^^

Impo
March 1st, 2011, 03:01 AM
i had my maths test today.
i feel pretty confident :) .

i know i got one question wrong though (i accidentally added the dividends instead of leaving them, so the answer was too big) .

but i managed to conquer the speed questions :D
they were actually fun :)

thanks for all the help on here, too :)

smile!
March 2nd, 2011, 03:01 PM
i had my maths test today.
i feel pretty confident :) .


I had my Calculus test yesterday as well :P And I felt it was better than the first one. At least I could answer all questions. XD

Although, I did one silly mistake by separating integral cos x sin x into integral cos x times sin x. =\ I thought you could do so, and only after the test when I checked I found out you cannot. >.<

NurseBarbra
March 8th, 2011, 11:35 AM
AND I GOT MY SAMPLE EXAM PAPER...
http://examinations.ie/schools/Project_Maths_Phase_2_P2_Higher_Level.pdf
Anyone wanna have a go at it?

Rossay
March 9th, 2011, 07:26 AM
I'll join, I tutor maths as a part-time job, so feel free to ask for help lol.

Username: Rossay
Overall Education Level: Undergraduate
Mathematics Education Level (Or most recent/advanced math subject): University
Do you think you can be asked for help in your level or lower?: Sure.

I like Pokemon (...)
March 14th, 2011, 10:18 AM
I'm surprised no one's mentioned it- HAPPY PI DAY!
Ah, Pi.... How awesome it is.
Only, it seems some people disagree (http://www.pokecommunity.com/tauday.com).

Spinor
March 18th, 2011, 03:11 AM
Happy seriously late Pi day and St. Patrick's day.....


... Well, a good topic would be to ask of all of you what you think of the concept of Tau, now that's it's nicely brought up. I think there can definitely be decent ways for Tau and Pi to coexist.

NurseBarbra
March 18th, 2011, 06:11 AM
Tau and Pi have to co-exist, Or else nothing would work. The universe is one of these things where if they are each constant seperatally, they must be constant together.

ShinyMeowth
March 18th, 2011, 11:28 AM
Pi is well-known all over the world. Ditching it is just going to confuse people. It would be a huge inconvenience. I have read the article and understood what the guy was thinking, but my opinion is he is just a bit crazy.

I do not see the point in celebrating "Pi day". Sure, the number is useful, but I don't understand why it could have a fanbase. After all, Mathematics is definitely not about just constants, so celebrating it here is actually just an insult to our intelligence.

Dude22376
March 18th, 2011, 09:58 PM
Had a look through that test paper. Did some of the questions, the non-Statistics ones because they can be done without stats software.

Q3

a) Substitute the coordinates of the point onto the equation of the line.
3(4k-2) - 4(3k+1) + 10
= 12k - 6 -12k - 4 + 10
= 0
b) The equation of l1 in the form y = mx + c is y = 3/4 x + 5/2
Gradient of l1 = 3/4
Gradient of l2 = -4/3
Equation of l2 : (y - 3k - 1)/(x - 4k + 2) = -4/3
Simplify: y = -4/3 x + 25/3 k -5/3
c) Substitute the values of x and y: 11 = -4/3 * 3 + 25/3 k -5/3
Simplify: k = 2
(Equation of line: y = 15 - 4/3 x, which (3,11) does lie on)
d) Foot of perpendicular = point of intersection
Equate y: 3/4 x + 5/2 = 15 - 4/3 x
Simplify: x = 6
Substitute into either line: y = 7


Q4

Equation of line in the form y = mx + c is y = -x/2 + 3
In order for the x- and y-axes to be tangents to the circle, the magnitudes of the x- and y-coordinates of the centre of the circle must be equal.

Proof:
Draw a circle which satisfies the conditions.
Draw a line perpendicular to each point of contact between the circle and the axes towards the centre of the circle.
The x- and y-axes, plus the two lines you just drew, form a square.
Being a circle, the two lines you drew are of equal length. As they are located on lines perpendicular to the x- and y-axes, this means that the magnitudes of the x- and y-coordinates of the centre of the circle must be equal.

This means that the centre of the circle must lie on the line y = x or y = -x.
Consider each case simultaneously:
Equate y: x = -x/2 + 3 or -x = -x/2 + 3 (Note that the first equation uses y = x, the second uses y = -x)
Solve for x: x = 2 or x = -6
Solve for y: y = 2 oy y = 6 (Note that the first equation uses y = x, the second uses y = -x)
This gives us the coordinates of the centres of the cricles, as well as the radius (which is equal to the magnitude of either coordinate of the centre).
Thus the equations of the circles are:
(x-2)^2 + (y-2)^2 = 4
(x+6)^2 + (y-6)^2 = 36


Q6B

Firstly, notice that the quadrilateral OECD is a cyclic quadrilateral.
Draw a circle in which OECD is inscribed.
We now claim that OC is equivalent to the diameter of the circle.

Proof:
From the centre of the circle (call this point Z), draw three lines connecting it to points O, D and C.
Since length of ZO=ZD=ZC, we can split ZODC into two isosceles triangles, ZOD and ZCD.
Thus angle ZOD=ZDO and angle ZDC=ZCD
Let angle ZOD=x and angle ZCD=y.
Then we can conclude the following about angles:
ZDO=x ZCD=y
OZD=180-2x CZD=180-2y
OZC=360-2x-2y=360-2(x+y)
Note that angle ODC=90=x+y
Thus OZC=180, and hence OC is a straight line.
The length of OC is the combined length of ZO and ZC, i.e. 2 times the radius, or equivalent to the diameter.

Consider the triangles ODC and EDC.
We now claim that angles DOC and DEC are equal.

Proof:
From the centre of the circle (call this point Z), draw three lines connecting it to points O, D and C.
Since length of ZO=ZD=ZC, we can split ZODC into two isosceles triangles, ZOD and ZCD.
Thus angle ZOD=ZDO and angle ZDC=ZCD
Let angle ZDC=a.
Then we can conclude that DOC=ZOD=ZDO=90-a (since ODC=90)
Now draw two lines connecting Z to points E, D and C.
Triangle EDC can be split into 3 equilateral triangles: ZED, ZDC, ZCE.
Maintaining that angle ZDC=a, we can conclude:
ZCD=a and DZC=180-2a
Let angle ZED=b and angle ZEC=c. We can conclude:
DEC=b+c
ZDE=b ZCE=c
DZE=180-2b CZE=180-2c
Consider the sum of angles ZDC,DZE and ZCE:
540-2a-2b-2c=360
Simplifying, b+c=90-a.
Since DOC=90-a and DEC=b+c, angle ZOC=DEC.

I like Pokemon (...)
March 19th, 2011, 07:20 AM
... Well, a good topic would be to ask of all of you what you think of the concept of Tau, now that's it's nicely brought up. I think there can definitely be decent ways for Tau and Pi to coexist.
I've not yet been taught Radians, or how they're used in Calculus, but I know what they are, and I think that Tau should be used in at least that instance.
I think with basic equations of the circle/sphere (circumference, area, surface area, volume) Pi is fine. It wouldn't really be any easier to remember with Pi or Tau.
Because I don't really use Pi that much (at this early stage) I'm not too bothered. If when I learn calculus or more complex trig, I might use Tau in my head, to understand it better.
I do not see the point in celebrating "Pi day". Sure, the number is useful, but I don't understand why it could have a fanbase. After all, Mathematics is definitely not about just constants, so celebrating it here is actually just an insult to our intelligence.
I "celebrate" it as more of a joke. Because Pi is so big, and so common in nature especially, it's almost like celebrating the beauty of nature and mathematics itself. That, and it gives me an excuse to eat pie.

Overlord Drakow
March 20th, 2011, 11:19 AM
I will join this club.

While I am here . . .

Anyone able to solve the Laplace Transform of;

1/(s^2 + 1)^0.5

Alakazam17
March 25th, 2011, 07:57 AM
Wow, this thread has been around for nearly two months and I'm just noticing it now. I'lll join as a full-pledge member, as I've always been a mathophile. XD

Username: Alakazam17
Overall Education Level: 3rd Year University
Mathematics Education Level: University level knowledge, between 2nd & 3rd year standing.
Do you think you can be asked for help in your level or lower?: Anything lower, definitely. As for my exact level, it'd be on a case-by-case basis.
Life = The Universe = Everything = : 42

And as for a math joke, I'll see if I can remember the just of this one made by my first year university professor:

lim sin(x)/n = 6
x->0

Anyone see what he did there? =D

Dude22376
March 26th, 2011, 12:14 AM
http://www.texify.com/img/%5CLARGE%5C%21%5Cnormalsize%20%5Clim_%7Bx%5Cto%5C0%7D%5Cfrac%7Bsin%20x%7D%7Bn%7D%3D%5Clim_%7Bx%5Cto%5C0%7D%5Cfrac%7Bsi%20%5Ccancel%7Bn%7D%20x%7D%7B%5Ccancel%7Bn%7D%7D%3D%5Clim_%7Bx%5Cto%5C0%7Dsix%3D6.gif

Another one:
ln e = 1
ln e = one
Cancel n and e from both sides:
1 = 0
This works better written out.

smile!
April 19th, 2011, 02:25 AM
This place is dying :(
Anyway, I just had my Calculus finals today. And one of the questions that I was soooo intrigued to solve (but so far haven't managed to do so yet) is this one:

Verify that
http://i263.photobucket.com/albums/ii159/arceus03/integral.png

I got pi/2, lol.

*whispers* ILPy, it's a pi! :P

Overlord Drakow
April 20th, 2011, 02:14 AM
Hmm alright I took a look into it using a computer package.

y = 1/(1 - x^2)^(1/2) + 2*(1 - x^2)^(1/2)

int(y)

ans = 2*asin(x) + x*(1 - x^2)^(1/2) [where asin(x) = arcsin(x)]

Substituting the limits gives;

2*pi/2 + 0 - 0 - 0 = pi

smile!
April 20th, 2011, 02:21 AM
Hmm alright I took a look into it using a computer package.

y = 1/(1 - x^2)^(1/2) + 2*(1 - x^2)^(1/2)

int(y)

ans = 2*asin(x) + x*(1 - x^2)^(1/2) [where asin(x) = arcsin(x)]

Substituting the limits gives;

2*pi/2 + 0 - 0 - 0 = pi

Yes, WolframAlpha says the same thing. But how do you prove it? And we didn't learn about arcsin yet. Is there a way to solve it yourself without computer help, do you know?

Overlord Drakow
April 20th, 2011, 02:28 AM
There's probably some trigonometric property you needed to know lol. I'll check my formula book now . . .

1/(1-x^2)^1/2 = sin^-1(x)

That's the property you needed.

smile!
April 20th, 2011, 04:17 AM
There's probably some trigonometric property you needed to know lol. I'll check my formula book now . . .

1/(1-x^2)^1/2 = sin^-1(x)

That's the property you needed.

>.< Yeah, I got that. But I got stuck after this
http://i263.photobucket.com/albums/ii159/arceus03/equation.png

5. 3 sin^-1 (x)], x=0 to 1 + .....?

The 2x^2 should be manipulated somehow. I tried using the identity (integral [du/(a^2-u^2)^1/2] = sin ^-1 u/a), but it doesn't work. I think that's because a is a constant, and not a variable. I used 1/x^2 for a, and 1/x for u. :P

Overlord Drakow
April 20th, 2011, 08:46 AM
You give me no choice. Here is an outline to the solution.

http://img198.imageshack.us/img198/4471/integralproblem.png

smile!
April 20th, 2011, 11:12 AM
You give me no choice. Here is an outline to the solution.

http://img198.imageshack.us/img198/4471/integralproblem.png

Umm. But we didn't learn about arcsin yet. Ergo, the solution should be something that doesn't use arcsin at all. Thanks for giving the solution anyway. I appreciate that :)

Overlord Drakow
April 20th, 2011, 11:16 AM
I have no idea how to solve it without using those trig properties then V_V

Dude22376
April 23rd, 2011, 05:55 PM
Arcsin is the inverse function of sin, you might have seen it written as sin^-1.
e.g. sin pi/2 = 1, so arcsin 1 = pi/2.
Note that the range of arcsin x is -pi/2 to pi/2, so arcsin 1 = pi/2 and not, say, 5 pi/2 (even though sin 5 pi/2 = 1)

For me, instead of turning t back into x, I changed the limits and evaluated based on t:

Let x = sin t.
dx/dt = cos t
dx = cos t dt

First we change the upper and lower limits from x to t. arcsin 0 = 0 and arcsin 1 = pi/2.

http://www.texify.com/img/%5Cnormalsize%5C%21%5Cint%20%5Climits_0%5E1%202sqrt%7B1-x%5E2%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B1-x%5E2%7D%7D%20dx.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%282sqrt%7B1-%5Csin%5E2t%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B1-%5Csin%5E2t%7D%7D%29%20%5Ccos%20t%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%282sqrt%7B%5Ccos%5E2t%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B%5Ccos%5E2t%7D%7D%29%20%5Ccos%20t%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%202%7B%5Ccos%5E2t%7D%20%2B%201%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%5Ccos%20%7B2t%7D%20%2B%202%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cfrac%20%7B%5Csin%7B2t%7D%7D%7B2%7D%20%5Cmiddle%7C%20_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%2B%202t%20%5Cmiddle%7C_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D.gif
= 0 - 0 + pi - 0
= pi

PROTIP
If you see sqrt(a^2-x^2), try to sub in x = a sin t.
For sqrt(x^2-a^2), sub in x = a sec t.
For sqrt(a^2+x^2), sub in x = a tan t.

@Drakow: Nitpicking here. It's incorrect to use 1 and 0 as the upper/lower limits after subbing x for t. You must either change the limits (as I did), or start off with the indefinite integral for x so that you don't need to write the limits for t.

Overlord Drakow
April 24th, 2011, 12:26 AM
Arcsin is the inverse function of sin, you might have seen it written as sin^-1.
e.g. sin pi/2 = 1, so arcsin 1 = pi/2.
Note that the range of arcsin x is -pi/2 to pi/2, so arcsin 1 = pi/2 and not, say, 5 pi/2 (even though sin 5 pi/2 = 1)

For me, instead of turning t back into x, I changed the limits and evaluated based on t:

Let x = sin t.
dx/dt = cos t
dx = cos t dt

First we change the upper and lower limits from x to t. arcsin 0 = 0 and arcsin 1 = pi/2.

http://www.texify.com/img/%5Cnormalsize%5C%21%5Cint%20%5Climits_0%5E1%202sqrt%7B1-x%5E2%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B1-x%5E2%7D%7D%20dx.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%282sqrt%7B1-%5Csin%5E2t%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B1-%5Csin%5E2t%7D%7D%29%20%5Ccos%20t%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%282sqrt%7B%5Ccos%5E2t%7D%20%2B%20%5Cfrac%7B1%7D%7Bsqrt%7B%5Ccos%5E2t%7D%7D%29%20%5Ccos%20t%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%202%7B%5Ccos%5E2t%7D%20%2B%201%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cint%20%5Climits_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%5Ccos%20%7B2t%7D%20%2B%202%20dt.gif
http://www.texify.com/img/%5Cnormalsize%5C%21%3D%20%5Cfrac%20%7B%5Csin%7B2t%7D%7D%7B2%7D%20%5Cmiddle%7C%20_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%20%2B%202t%20%5Cmiddle%7C_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D.gif
= 0 - 0 + pi - 0
= pi

PROTIP
If you see sqrt(a^2-x^2), try to sub in x = a sin t.
For sqrt(x^2-a^2), sub in x = a sec t.
For sqrt(a^2+x^2), sub in x = a tan t.

@Drakow: Nitpicking here. It's incorrect to use 1 and 0 as the upper/lower limits after subbing x for t. You must either change the limits (as I did), or start off with the indefinite integral for x so that you don't need to write the limits for t.

What you say is true, however, because the substitution reverts back to x anyway, I did not bother changing the limits just to change them back to the original limits. Though you are right, I am mathematically wrong. Anyway, I think your solution is probably the one he was expected to give for his exam.

smile!
April 25th, 2011, 12:58 AM
Arcsin is the inverse function of sin, you might have seen it written as sin^-1.

...
...
...

*fails at life* How come I never knew that before? >.<
Okay, so everything makes sense now. Thanks, Drakow & Dude22376 =)

Overlord Drakow
April 25th, 2011, 01:38 AM
^Dude! I implied that to you in my earlier message when I gave you the property you needed.

Ah, we all make these mistakes. I doubt you'll ever forget that again lol.

smile!
April 25th, 2011, 10:35 PM
^Yeah, I just didn't realize it. lol. XD Thanks again :P

RASENCERO
May 4th, 2011, 10:16 AM
This club needs a logo:
http://www.vestdijkfraneker.nl/Wiskunde/math.gif
(http://www.vestdijkfraneker.nl/Wiskunde/math.gif)

If you like math jokes:
http://www.aquabacon.com/wp-content/main/2009_09/math-jokes.jpg
(http://www.aquabacon.com/wp-content/main/2009_09/math-jokes.jpg)

Or just google for stuff.
Go solve (infinite) continued fractions or something.

*Teleports out*

Overlord Drakow
May 27th, 2011, 03:57 PM
What did the constipated Mathematician do to solve his/her problem?

Lifes-A-Beach
June 1st, 2011, 11:43 AM
I've always loved Math, so I would love to be a Full-Pledge Member here :)
I hate how school policies can only hold me back from my potential :(

Username: Lifes-A-Beach
Overall Education Level: 9th Grade (USA)
Mathematics Education Level (Or most recent/advanced math subject): Algebra II / Trigonometry H (School), Pre-Calculus (Independently)
Do you think you can be asked for help in your level or lower?: No (Unfortunately, I don't have much spare time on top of all my other Honors Courses :( )
Life = The Universe = Everything = : 42 is never wrong

Bela
June 10th, 2011, 12:07 AM
ATTENTION ALL YOCTOGRAMS!

http://i52.tinypic.com/29tuys.png

Make Sho Minamimoto your club mascot! You won't regret it for one millisecond!

Username: Sho Minamimoto Bela
Overall Education Level: Undergraduate
Mathematics Education Level (Or most recent/advanced math subject): Most recent math class is a Finite Math hodgepodge class for transfer credit. Crunch! I'll add it to the heap (of credits I have!)
Do you think you can be asked for help in your level or lower?: Let's see the limit of U as I go to infinity!
Life = The Universe = Everything = 3 is the point of the 1. 4 the 1-5-9 are 2. 6-5, 3-5! 8-9, 7-9! 32384 62643 38327! And...perfect.

Renii
June 11th, 2011, 01:08 AM
Full pledged Membership for me too =)
Username: Renii
Overall Education Level: About to finish high school. =)
Mathematics Education Level (Or most recent/advanced math subject): Calculus, I think.
Do you think you can be asked for help in your level or lower?: Yeah. I think so.
Life = The Universe = Everything = : Forty twoooooiooo

Spinor
June 22nd, 2011, 12:17 AM
LIST UPDATED! CHEESEUS SWISS CHRIST STOP BUGGING ME! ;_;

What did the constipated Mathematician do to solve his/her problem?

I only revived the club because I wanted to hear the end of this one.

Renii
June 22nd, 2011, 12:23 AM
LIST UPDATED! CHEESEUS SWISS CHRIST STOP BUGGING ME! ;_;



I only revived the club because I wanted to hear the end of this one.
S/He works it out with a pencil... =_=

Meh, this place is *dead*...

Spinor
June 22nd, 2011, 12:29 AM
S/He works it out with a pencil... =_=

Meh, this place is *dead*...

Beautiful. Let's talk about APs and finals.

So I'm nervouse about my AP Cal result. My principle is being a dick and says if I don't get a 5, I can't skip Cal AB. Sonofagun test felt like a 4. At least I'll also be taking AP stats next year. 4 APs my Sophomore year, I feel brave and insane.

Oh, I also took the liberty of updating everyone's membership to their next logical grade level and math level.

Renii
June 22nd, 2011, 12:40 AM
What are APs? And a 5, cal AB O.o

I live in a different country, we have a totally different education system.

Spinor
June 22nd, 2011, 12:46 AM
What are APs? And a 5, cal AB O.o

I live in a different country, we have a totally different education system.

APs = Advanced Placement tests/courses (depending on context), brought to you by the same guys who dish out the SATs. And yes, you've heard about those rare 5's on the Calculus AB tests? Not even MIT is punk enough to demand a 5 on that test, just a 4.

Overlord Drakow
June 22nd, 2011, 04:34 AM
Renii is correct.

Hey! You need to add me to the list of fully pledged Mathematicians! Fine . . . I'll fill your form out..

Username: Drakow
Overall Education Level: Finished undergraduate.
Mathematics Education Level - BSc Mathematics - First Class
Do you think you can be asked for help in your level or lower?: If anyone needs help, feel free to drop me a line and I'll do the best I can to sort things out.

Bela
July 2nd, 2011, 02:57 AM
∫ e^x = f (u)^n

:)

Hope everybody's 4th of July weekend is great!

Masters Cage
July 6th, 2011, 03:32 PM
Username: Masters Cage

Overall Education Level: Year 10 in High School

Mathematics Education Level (Or most recent/advanced math subject): Top class for Maths, never failed a Maths test, doing the hardest Maths course next year at school and TAFE (Maths 2-Unit and Extended Maths)
Do you think you can be asked for help in your level or lower?: Hell Yeah, I get asked about Maths all day at school....

And before you all ask, No.... I'm not a nerd, I play sports and other stuff, it just so happens I'm really good at Maths for a 16 year old....

smile!
August 5th, 2011, 10:29 AM
It's exactly been 30 days. Hope I'm not breaking the rules. (Since it said... more than 30 days. :P)

Anyway. Just checking, with only the data given, is it possible to solve this problem... at all? o.o

Let Chords AB and CD of Circle O intersect at Point E. BE=x, EA=3x-1, DE=x-1, CE=4x. Find the lengths of AB and CD.

The way I see it, only in terms of x... right?

Renii
August 6th, 2011, 07:38 AM
It's exactly been 30 days. Hope I'm not breaking the rules. (Since it said... more than 30 days. :P)

Anyway. Just checking, with only the data given, is it possible to solve this problem... at all? o.o

Let Chords AB and CD of Circle O intersect at Point E. BE=x, EA=3x-1, DE=x-1, CE=4x. Find the lengths of AB and CD.

The way I see it, only in terms of x... right?
Read this http://en.wikipedia.org/wiki/Cyclic_quadrilateral#Diagonals and you'll get x = 3

:P

smile!
August 6th, 2011, 08:22 AM
Read this http://en.wikipedia.org/wiki/Cyclic_quadrilateral#Diagonals and you'll get x = 3

:P

Aaaah.

Great, thanks a bunch! XD

Snow Phoenix
August 10th, 2011, 07:33 AM
Well, I sure forgot about this place @-@ Nyeh... I remembered it because I have somewhat mehish news.

I only have two more math classes left until I've finished all of the math I need in college :/ Calculus II and Stats. Everything after would be an empty credit. So I'm quite sad, yet happy.

Ascaris
August 15th, 2011, 03:56 PM
Username: i dont know
Overall Education Level: 12th grade
Mathematics Education Level (Or most recent/advanced math subject): im pretty much thorough on all forms of algebra, euclidean and cartesian geometry and basic multivariable calculus.
Do you think you can be asked for help in your level or lower?: sure. as long as you dont ask me questions about statistics. i hate statistics.

Corvus of the Black Night
August 26th, 2011, 01:06 PM
Username: Corvidae
Overall Education Level: Going into Freshman year college next year
Mathematics Level (Or most recent/advanced math subject): I took stats and calculus, but I was horrible at stats and my calculus is rusty.
Do you think you can be asked for help in your level or lower?: Pre-calc and I'm there. I'm taking calculus in college again for a reason.

2Cool4Mewtwo
September 15th, 2011, 07:02 PM
This thread needs a deserved bump :)

Username: 2cool4mewtwo
Overall Education Level: Senior in high school.
Mathematics Education Level (Or most recent/advanced math subject): AP Calculus BC, AP Statistics
Do you think you can be asked for help in your level or lower?: Calc AB I'm somewhat comfortable with, though I'm not that reliable on what I'm learning right now :P

Impo
September 16th, 2011, 06:19 PM
I remember posting here before, don't know why I stopped...

Anyways, I've got my advance math classes these days, and they are just so unappealing.
Stupid Differential Calculus or whatever it's called.

I'm stuck on these questions, I'm afraid to admit, I need to work over them again x)

Snow Phoenix
September 16th, 2011, 06:42 PM
I remember posting here before, don't know why I stopped...

Anyways, I've got my advance math classes these days, and they are just so unappealing.
Stupid Differential Calculus or whatever it's called.

I'm stuck on these questions, I'm afraid to admit, I need to work over them again x)
Ooo! I took that last semester at the community college I attend :3 I might be able to help :D I made an A in the class and I'm currently in Integral Calculus myself.

smile!
September 16th, 2011, 08:09 PM
Ahh. Calculus. XD I took that last... spring. I might have to take it again in the winter quarter. I need some practice, I'm already rusty. =\

Renii
September 16th, 2011, 11:46 PM
I'm studying calculus right now. I might be able to help as well.

In fact, I have an exam based on Differentiation and Integration in a few days.

Overlord Drakow
September 17th, 2011, 04:11 AM
Feel free to post the problems you are stuck on and I can give them a go.

Renii
September 19th, 2011, 03:07 AM
Could you guys give this question a try:

http://i.imgur.com/BJicO.gif

I was able to integrate it using the substitution t^20 = x and got a long answer. Is there an easier way to solve it?

Overlord Drakow
September 19th, 2011, 04:12 AM
I do not think so. I gave it some thought but nothing springs to mind. That is one seriously nasty integral though ¬___________¬

Renii
September 19th, 2011, 04:58 AM
I know.

I just hope they aren't gonna give questions like that on the test :/

Overlord Drakow
September 20th, 2011, 02:26 AM
I've been doing some more thinking on your problem and have come up with a possible simplification.

You could try the substitution t = x^k^-1, where k is any real number.

What that does is inverse the power so you still end up with t^5 and t^4 on the denominator but it should simplify the numerator and make the integrand easier to tackle. I haven't run through the maths or anything but if you want, try it and see.

Renii
September 20th, 2011, 03:27 AM
You mean take t = x^(1/20)? (t = x^20^-1 ?)

I tried that, gives a long answer. It requires applying the binomial theorem with a power of 15)

Or something else like t = 1/x^k? How? :/

Overlord Drakow
September 21st, 2011, 01:45 PM
I meant what I typed out exactly.

t = x^k^-1

So for the first term you have x^(1/5) so the transformation gives t^5 and the second term goes from x^(1/4) to t^4

If that makes sense.

Edit: The transformation inverses the power of x or in other words you flip the fractions over.