\(\begin{array} \ -1\leq\sqrt3\tan x \leq1 \\~\\ -1\leq\sqrt3\tan x&\qquad&\sqrt3\tan x \leq 1 \\~\\ -\frac{1}{\sqrt3}\leq\tan x &\qquad& \tan x \leq \frac{1}{\sqrt3} \\~\\ -\frac{\sqrt3}{3}\leq\tan x &\qquad& \tan x \leq \frac{\sqrt3}{3} \\~\\ \arctan(-\frac{\sqrt3}{3}) \leq x &\qquad& x \leq \arctan(\frac{\sqrt3}{3}) \\~\\ -30^{\circ}+180^{\circ}n \leq x &\qquad& x \leq 30^{\circ}+180^{\circ}n \qquad\text{, where n is an integer}\\~\\ -30^{\circ}\leq x-180^{\circ}n &\qquad&30^{\circ}\leq x-180^{\circ}n \\~\\ -30^{\circ}\leq x-180^{\circ}n\leq30^{\circ}\end{array}\)
So...for instance...
-30º ≤ x ≤ 30º
150º ≤ x ≤ 210º
330º ≤ x ≤ 390º
I think this is right, but I am not 100% confident in this answer...