Trigonometric Functions And Equations

$\left\{2 n \pi+\frac{\pi}{3}: n \in I\right\}$

$\left\{n \pi \pm \frac{\pi}{2}: n \in I\right\}$

$\left\{n \pi+\frac{\pi}{4}: n \in I\right\}$

$\left\{2 n \pi-\frac{\pi}{3}: n \in I\right\}$