heres the problem: http://img186.imageshack.us/img186/4328/untitledil5.jpg

i marked where i'm having trouble.

I don't see how this was integrated.

can someone break it down further, for the part i marked.

thanks

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- February 18th 2007, 08:29 PMrcmangohelp with integral
heres the problem: http://img186.imageshack.us/img186/4328/untitledil5.jpg

i marked where i'm having trouble.

I don't see how this was integrated.

can someone break it down further, for the part i marked.

thanks - February 18th 2007, 08:43 PMThePerfectHacker
- February 18th 2007, 10:19 PMrcmango
[QUOTE=1-cos 2x and then that easily integrates.QUOTE]

so then using the trig identity, sinx^2 + cosx^2 = 1

1 - cos2x is the integral.

i'm going to guess what the derivative is, may need help, tried using mathematica.

hmm not sure why x is dived by 2, wheres the 1/4 coming from? .. x/2 - 1/4sin(2x) + c

thanks for all the help so far. - February 19th 2007, 08:34 AMThePerfectHackerQuote:

so then using the trig identity, sinx^2 + cosx^2 = 1

1 - cos2x is the integral.

i'm going to guess what the derivative is, may need help, tried using mathematica.

hmm not sure why x is dived by 2, wheres the 1/4 coming from? .. x/2 - 1/4sin(2x) + c

thanks for all the help so far.

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

cos^2(x/2)=(1/2)(1+cos x)