integrating and differentiating sin^2(x) and cos^2(x) (1 Viewer)

helz_h

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Help. I simply can't do this. I have the wrong formula in my notes and would be very appreciative of someone correcting it!

Thanks a million!
 

Trev

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d/dx * sin<sup>2</sup>x = 2cosx.sinx
d/dx * cos<sup>2</sup>x = -2sinx.cosx

Like you know how cos<sup>2</sup>x+sin<sup>2</sup>x=1
d/dx * [cos<sup>2</sup>x+sin<sup>2</sup>x] = d/dx * 1
2cosxsinx - 2sinxcosx = 0
0 = 0
 

onebytwo

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for integration
make since cos2x=(1/2)(1+cos2x)...then integrate
do the same thing for sine
 

m0ofin

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Use the function of a function rule after you take the square out.
y = sin2x
y = (sinx)2
y' = 2cosx.sinx

Same for cosx
 

helz_h

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thanks for your help!

Good luck with your exams :)
 

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