How do you verify the identity #sin(x+y)sin(x-y)=sin^2x-sin^2y#?
1 Answer
Feb 17, 2017
Consider the trig identities:
sin (x + y) = sin x.cos y + sin y.cos x
sin (x - y) = sin x.cos y - sin y.cos x
Applying the algebraic identity:
product becomes:
Replace
We get: