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