Question

sin (W + c). sin (W - c) = _​

Answer 1

Answer:

$\frac{1}{2} ( - cos(2W) + cos (2c))$

Step-by-step explanation:

Using

cos C - cos D = $- 2 \ \sin( \frac{c + d}{2} ) \sin( \frac{c - d}{2} )$