How do you evaluate sec^-1(sec((11pi)/6))?

$\frac{11 \pi}{6}$
${\sec}^{-} 1 \text{ and" sec "are " color(blue)"inverse functions}$
and in general $\textcolor{red}{| \overline{\underline{\textcolor{w h i t e}{\frac{a}{a}} \textcolor{b l a c k}{{f}^{-} 1 \left(f \left(x\right)\right) = x} \textcolor{w h i t e}{\frac{a}{a}} |}}}$
$\Rightarrow {\sec}^{-} 1 \left(\sec \left(\frac{11 \pi}{6}\right)\right) = \frac{11 \pi}{6}$