Question

1) sin^2 (п/2+a)- sin^2 ( п-а)

Answer 1

Ответ:

$\sin {}^{2} ( \frac{\pi}{2} + \alpha ) - \sin {}^{2} (\pi - \alpha ) = \cos {}^{2} ( \alpha ) - \sin {}^{2} ( \alpha ) = \cos(2 \alpha )$