Arccsc
From specialfunctionswiki
The function $\mathrm{arccsc} \colon \mathbb{R} \setminus (-1,1) \rightarrow \left[ -\dfrac{\pi}{2}, \dfrac{\pi}{2} \right] \setminus \{0\}$ is the inverse function of the cosecant function.
Domain coloring of $\mathrm{arccsc}$.