Question

$sin^{2}$45° - $cos^{2}$60°

Answer 1

Ответ:

$\sin {}^{2} (45 ^ {\circ}) - \cos {}^{2} (60 ^ {\circ}) = {( \frac{ \sqrt{2} }{2} )}^{2} - {( \frac{1}{2} )}^{2} = \\ = \frac{1}{2} - \frac{1}{4} = \frac{1}{4} = 0.25$