## Calculus 8th Edition

$\frac{\pi}{3},\frac{2\pi}{3},\frac{4 \pi}{3}\frac{5 \pi}{3}$
Need to find the range for $x$ for the equation $3cot^{2}x=1$ $cot^{2}x=\frac{1}{3}$ or $tan^{2}x=3$ gives $tanx=±\sqrt 3$ Since, $tanx>0$ on first and third quadrant and $tanx<0$ on second and fourth quadrant, thus, x must lie on $\frac{\pi}{3},\frac{2\pi}{3},\frac{4 \pi}{3}\frac{5 \pi}{3}$