Answer
$s = \{-\frac{11\pi}{6}, -\frac{7\pi}{6}, -\frac{5\pi}{6}, -\frac{\pi}{6}, \frac{\pi}{6}, \frac{5\pi}{6}\}$
Work Step by Step
$3~tan^2~s = 1$
$tan^2~s = \frac{1}{3}$
$tan~s = \pm \frac{1}{\sqrt{3}}$
Since $\frac{y}{x} = \pm \frac{1}{\sqrt{3}}$, the angle $s$ makes an angle of $\frac{\pi}{6}$ with the x-axis.
In the interval $[-2\pi, \pi)$:
$s = \{-2\pi+\frac{\pi}{6}, -\pi-\frac{\pi}{6}, -\pi+\frac{\pi}{6}, -\frac{\pi}{6}, \frac{\pi}{6}, \pi-\frac{\pi}{6}\}$
$s = \{-\frac{11\pi}{6}, -\frac{7\pi}{6}, -\frac{5\pi}{6}, -\frac{\pi}{6}, \frac{\pi}{6}, \frac{5\pi}{6}\}$