If $A = \begin{bmatrix} 2i & i^3 \\ i^2 & 1 \end{bmatrix}$, then $A^{-1}$ is equal to

The minimum value of $(\sin^{-1} x)^2 + (\cos^{-1} x)^2$ is............

If $\tan^{-1}(1) + \tan^{-1}(3) + \tan^{-1}(5) + \tan^{-1}\left(\dfrac{1}{4}\right) = \pi + \tan^{-1}\left(\dfrac{\alpha}{2}\right)$, then the value of $\alpha$ is...

The domain of the function $f(x) = \sqrt{x - 1} + \sqrt{3 - x}$ is ...