Level:
Project ID:
2010009805
Source Problem:
Accepted:
0
Clonable:
1
Easy:
0
The solution set of the inequality \( |\cos x| \leq \frac12 \) for \( x\in\mathbb{R} \) is:
\( \bigcup\limits_{k\in\mathbb{Z}}\left[\frac{\pi}3+k\pi;\frac{2\pi}3+k\pi\right] \)
\( \bigcup\limits_{k\in\mathbb{Z}}\left[-\frac{\pi}3+k\pi;\frac{\pi}3+k\pi\right] \)
\( \bigcup\limits_{k\in\mathbb{Z}}\left[\frac{\pi}3+k\pi; \infty\right) \)
\( \bigcup\limits_{k\in\mathbb{Z}}\left[\frac{\pi}3+k\pi;\frac{4\pi}3+k\pi\right] \)