List of top Mathematics Questions on Inverse Trigonometric Functions asked in UPSEE

If $\cos^{-1} \frac{3}{5} + \cos^{-1} \frac{12}{13} = \cos^{-1} k$, then the value of $k$ is
$\sin^{2}\,\theta\, \cos^{3}\,\theta-\sin^{4}\,\theta\, \cos\,\theta$ is equal