$1 + \cot^2(\sin^{-1}x) = $

Evaluate: $\cos^{-1} \left( \cos \frac{7\pi}{6} \right)$

Find the value of $\cos ^{-1}\left(\frac{1}{2}\right)+2 \sin ^{-1}\left(\frac{1}{2}\right)$

$\sin (\cot ^{ - 1}x) = $

Consider the following statements:
Statement-$I$: $\operatorname{Cosh}^{-1} x = \operatorname{Tanh}^{-1} x$ has no solution.
Statement-$II$: $\operatorname{Cosh}^{-1} x = \operatorname{Coth}^{-1} x$ has only one solution.
The correct answer is:

The principal value of $\cot ^{-1}\left(\frac{-1}{\sqrt{3}}\right)$ is