Задание
Решите уравнение:
\(2\cos x=-1\)
- \(\pm\frac{2\pi}{3}+2\pi n,n\in Z\)
- \(\frac{2\pi}{3}+2\pi n,n\in Z\)
- \(\pm\frac{\pi}{3}+2\pi n,n\in Z\)
- \(\frac{\pi}{3}+2\pi n,n\in Z\)