\[\boxed{\mathbf{611}\mathbf{.}}\]
\[1)\ tg\ 3x = 0\]
\[3x = arctg\ 0 + \pi n = \pi n\]
\[x = \frac{1}{3} \bullet \pi n\]
\[x = \frac{\text{πn}}{3}\]
\[Ответ:\ \ x = \frac{\text{πn}}{3}.\]
\[2)\ 1 + tg\frac{x}{3} = 0\]
\[\text{tg}\frac{x}{3} = - 1\]
\[\frac{x}{3} = arctg( - 1) + \pi n =\]
\[= - arctg\ 1 + \pi n = - \frac{\pi}{4} + \pi n\]
\[x = 3 \bullet \left( - \frac{\pi}{4} + \pi n \right)\]
\[x = - \frac{3\pi}{4} + 3\pi n\]
\[Ответ:\ x = - \frac{3\pi}{4} + 3\pi n.\]
\[3)\ \sqrt{3} + tg\frac{x}{6} = 0\]
\[\text{tg}\frac{x}{6} = - \sqrt{3}\]
\[\frac{x}{6} = arctg\left( - \sqrt{3} \right) + \pi n =\]
\[= - arctg\ \sqrt{3} + \pi n = - \frac{\pi}{3} + \pi n\]
\[x = 6 \bullet \left( - \frac{\pi}{3} + \pi n \right)\]
\[x = - 2\pi + 6\pi n\]
\[Ответ:\ x = - 2\pi + 6\pi n.\]