Solve operatorname{sh}wquadz^2+z^2/z^2leq2

$$\operatorname { sh } w \quad \frac { z ^ { 2 } + z ^ { 2 } } { z ^ { 2 } } \leq 2$$

Solve for w

$$\left\{\begin{matrix}w\geq \frac{1}{hs}\text{, }&\left(h<0\text{ and }s>0\text{ and }z\neq 0\right)\text{ or }\left(h>0\text{ and }s<0\text{ and }z\neq 0\right)\\w\leq \frac{1}{hs}\text{, }&\left(s>0\text{ and }h>0\text{ and }z\neq 0\right)\text{ or }\left(s<0\text{ and }h<0\text{ and }z\neq 0\right)\\w\in \mathrm{R}\text{, }&z\neq 0\text{ and }\left(h=0\text{ or }s=0\right)\\w=\frac{1}{hs}\text{, }&h\neq 0\text{ and }s\neq 0\text{ and }z\neq 0\end{matrix}\right.$$