Question

Can someone show the steps on how to establish this identity:
1- (sin²θ/1+cosθ) = cosθ

Answer 1

\(1-\frac{\sin^2 \theta}{1+\cos \theta} = \frac{1+\cos \theta-\sin^2\theta}{1+\cos\theta}\).
So,
\[
\frac{1+\cos \theta-\sin^2\theta}{1+\cos\theta} = \cos \theta
\]
if and only if
\[
1+\cos \theta-\sin^2\theta = \cos\theta + \cos^2\theta
\]
it's almost done now

Answer 2

let's try start from left side