Question

Найдите значение выражения

Answer 1

$frac{Cos2 pi*Cos beta +Sin2 pi *Sin beta-(Sin beta *Cos frac{3}{2} pi -Cos beta *Sin frac{3}{2} pi ) }{2(Cos beta *Cos pi +Sin beta *Sin pi )} =$ $frac{1*Cos beta +0*Sin beta-(0*Sin beta-(-1)*Cos beta ) }{2((-1)*Cos beta +0*Sin beta )} = frac{Cos beta -Cos beta }{-2Cos beta } =0$