Question

(sin(п/2+альфа)+sin(п+альфа))"2+2sin(п-2)*sin(п/2+альфа)

Answer 1

$( сos^{2} \alpha - sin^{2} \alpha )^{2} +2cos \alpha *sin \alpha = cos \ ^{2} \alpha - 2cos \alpha *sin \alpha + sin^{2} \alpha$$+2cos \alpha *sin \alpha = cos^{2} \alpha + sin^{2} \alpha =1;$