Question

Спростіть вираз:

1) cos(3pi/2+α)
2) cos(pi-α)
3) sin(180`+α)
4) sin^2(5pi/2+α)

Answer 1

$1)Cos(frac{3pi }{2}+alpha)=Sinalpha\\2)Cos(pi-alpha)=-Cosalpha\\3)Sin(180^{o}+alpha)=-Sinalpha\\4)Sin^{2}(frac{5pi }{2}+alpha)=Sin^{2}(2pi+frac{pi }{2}+alpha)=Sin^{2}(frac{pi }{2}+alpha)=Cos^{2}alpha$