#1

Well, are you? See if you can figure out this 12th grade math problem. I'm taking calculus and I need help from the bright minds on UG.

First problem: Use integration by parts to evaluate integral of arccos(2x)dx.

My guess is

u=arccos2x, dv=dx, du=-1/(1-x^2), v=x

("?" in this case is integral symbol)

uv-?(vdu) = x(arccos(2x)) + ?(x/((1-x^2)^(1/2)))

but that's as far as I got.

Second problem: Evaluate the integral of 2cos(ln(t))dt by using a substitution prior to integration by parts.

First problem: Use integration by parts to evaluate integral of arccos(2x)dx.

My guess is

u=arccos2x, dv=dx, du=-1/(1-x^2), v=x

("?" in this case is integral symbol)

uv-?(vdu) = x(arccos(2x)) + ?(x/((1-x^2)^(1/2)))

but that's as far as I got.

Second problem: Evaluate the integral of 2cos(ln(t))dt by using a substitution prior to integration by parts.

*Last edited by yoshixxx7 at Mar 9, 2007,*

#2

what the **** is an 'integralof'???

#3

^^ 'Integral of'...?

If you'd asked me that a year or two ago I would have been able to answer that no problems. I've got an A in A level maths, but I've not as much as thought about Intergration since then!

If you'd asked me that a year or two ago I would have been able to answer that no problems. I've got an A in A level maths, but I've not as much as thought about Intergration since then!

#4

what the **** is an 'integralof'???

Ok I fixed that issue. I didnt have the symbol ? on my keyboard so I had to search for it on google.

EDIT: Wow it doesnt show the symbol....

#5

How old is a 12 grader?

#6

I dropped out of calc...

#7

Oh, sorry. i cant help. Is 12th grade not the equivalent of year 12?

I usually use this website when im stuck though, its really useful but im not sure if it goes past A level

www.mathsnet.net

I usually use this website when im stuck though, its really useful but im not sure if it goes past A level

www.mathsnet.net

#8

i AM a 12th grader!

#10

i'm in grade 11

thanks alot for discourageing me completely

thanks alot for discourageing me completely

#11

Year 12?

Eh, I dont feel so stupid then

Eh, I dont feel so stupid then

#12

to answer the title of this thread yes i am

#13

I'm at University, and I don't think I can understand that. They just make some simple stuff overly complicated. Karnaugh maps etc..

#14

Well as I passed grade 12 and am now first university, I would think so.

However, I must applaud you on your attempt to get UG'ers to do your math homework.

However, I must applaud you on your attempt to get UG'ers to do your math homework.

#15

boy, thanks for ruining maths for me, now i'll never take it for my A level

#16

Well as I passed grade 12 and am now first university, I would think so.

However, I must applaud you on your attempt to get UG'ers to do your math homework.

Indeed. I'd consider helping had I not been doing this stuff this morning.

#17

Try the couple steps up from that stuff... Not fun.Indeed. I'd consider helping had I not been doing this stuff this morning.

#18

Year 12?

Eh, I dont feel so stupid then

Grade 12 is 6th year I believe. http://www.answers.com/topic/twelfth-grade

You crazy Europeans with your grade system.

#19

In the country on Quebec we don't have twelve grades, we're better than other people because of that.

#20

12th grade is Senior year, so you'd be 17 or 18. And **** that, I'm in 12th grade and I don't know that..then again, I'm not taking any math classes this year.

#21

12th Grade is the equivalent of year 13

#22

I took statistics instead of calc.

#23

isnt derivative of arccos(2x)= 1/sqrt(1-4x^2)? but anyways im tryin to work it out

#24

i think in the first one you have to do an integration by parts again.... on the second one im not sure but its friday and i dont wanna do i anymore