## Trigonometry (11th Edition) Clone

$0$
Inverse Secant Function: $y=\sec^{-1}x$ or $y=$ arcsec $x$ means that $x=\sec y$, for $0 \leq y \leq \pi, y\displaystyle \neq\frac{\pi}{2}$. ---------------- $\displaystyle \sec 0=\frac{1}{\cos 0}=\frac{1}{1}=1,$ and $0 \leq$0$\leq \pi,$ 0$\displaystyle \neq\frac{\pi}{2}$, so $y=\sec^{-1}1=0$