Need to find all solutions of this

$\displaystyle Tan^2 x = 1$

Book says $\displaystyle {\pi\over 4} + {\pi\over 2}N$

But its $\displaystyle Tan x = 1$ and $\displaystyle Tan x = -1$

So shouldnt the reference angle ($\displaystyle \pi\over 4$) be in every quadrant?