Question

AP mth

Answer 1

do you know what cos(2x) equals to?

Answer 2

no

Answer 3

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

Answer 4

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

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

now just solve for sin^2(x)

Answer 5

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

Answer 6

well yeah that's what you're supposed to show

Answer 7

hmm