Question

I am grateful for any help! Assume that θ is a positive acute angle.

Given: cosθ = 40/41

Find: sin2θ

Answer 1

720/1681

Explanation:

if cos(x)= 40/41

then sin(x) = 9/41.

then sin(2x)= 2 sinx. cosx

= 2*40*9/41*41

= 720/1681