$$\left. \begin{array} { l } { 2 + 2 \tan \theta = \sec ^ { 2 } \theta , } \\ { 2 + 2 \tan \theta = \sec ^ { 2 } \theta , } \end{array} \right.$$
$\theta =\frac{\pi n_{1}}{2}+\frac{3\pi }{8}$
$n_{1}\in \mathrm{Z}$
