求解 tan(x)^2=4

$${ \tan ( x ) } ^ {2} = 4$$

求解 x 的值

$$x=\pi n_{1}+\arctan(2)\text{, }n_{1}\in \mathrm{Z}$$

$$x=\pi n_{2}+\pi -\arctan(2)\text{, }n_{2}\in \mathrm{Z}$$