Question

Спростіть вираз:

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

Answer 1

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