Learn how to solve problems step by step online. Prove the trigonometric identity tan(a/2)(cos(a)+1)=sin(a). Starting from the left-hand side (LHS) of the identity. Rewrite \tan\left(\frac{a}{2}\right) in terms of sine and cosine. Multiplying the fraction by \cos\left(a\right)+1. Solve the product of difference of squares \left(1-\cos\left(a\right)\right)\left(\cos\left(a\right)+1\right).

Prove the trigonometric identity tan(a/2)(cos(a)+1)=sin(a)