Question

Упростите выражение:
sin(a + B) - sin(a — B) ​

Answer 1

$sin(alpha +beta )-sin(alpha -beta )=2cdot sinfrac{(alpha +beta )-(alpha -beta )}{2}cdot cosfrac{(alpha +beta )+(alpha -beta )}{2}=\\=2cdot sinbeta cdot cosalpha$