# integrate things for me!!

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#1
who are the lovely people who want to integrate

cos^2(x)

sin^2(x)

please - my p3 exam is tomorrow - eek!!!!

rep if you want it!!
0
15 years ago
#2
i wont do them but

use the cos2x = 2cos^2 x - 1 = 1 - 2sin^2 x

(yes i would like rep )
0
15 years ago
#3
I will not do the whole method for you but the idea is to use trig identities; we have

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

Which means that

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

Rearranging gives

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

which you can use to integrate sin^2(x) and cos^2(x). I hope this helps.
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