Задание

Решите уравнение:

\(2\cos x=-1\)

\(\pm\frac{2\pi}{3}+2\pi n,n\in Z\)

\(\frac{2\pi}{3}+2\pi n,n\in Z\)

\(\pm\frac{\pi}{3}+2\pi n,n\in Z\)

\(\frac{\pi}{3}+2\pi n,n\in Z\)