In $\triangle ABC$, if $a = 13, b = 14, c = 15$, then the value of $\sin A + \cos A$ is...

If the matrix $A = \begin{bmatrix} 4 & 1 \\ 3 & 2 \end{bmatrix}$ is expressed as the sum of a symmetric matrix B and a skew symmetric matrix C then which of the following relations is correct?

If $A$ is a non-singular matrix and $A^2 - A + I = 0$, then $A^{-1} = \ldots$

The value of $3\tan^{-1}\left(\dfrac{1}{2}\right) = \ldots$