Question #3acab

1 Answer
May 14, 2017

see explanation

Explanation:

using right triangle with a vertex at the origin and angle
θ, with sides corresponding to θ

adjacent =x, opposite =y, hypotenuse =r

sinθ=yr,cosθ=xr and r2=x2+y2

1sin2θ=1y2r2=r2r2y2r2

1sin2θ=r2y2r2=x2r2=cos2θ