Question

does 1/2sin^2x= -1/4 cos(2x)

Answer 1

Expand out both sides to see if that's true

Answer 2

not sure if I know how to do that..

Answer 3

cos(2x)=cos(x+x). now tell me how to expand the right hand side?

Answer 4

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

cos(2X)=1-2sin^2x so..
2sin(x)^2=2sin(x)^2-1 ?

Answer 5

yeah, actually. you're done!

Answer 6

so not equal... :(

Answer 7

does

Answer 8

yeah, you arrived at a contradiction and it can't be true.

Answer 9

\[\int\limits_{?}^{?} cosxsinx dx\] = which one?

Answer 10

integral of cosx * sinx dx I got the 1/2 sin^2(x) but my answer key I have the other one