If $$ A = ( a_{ij} )_{n \times n }$$ and $$f$$ is a function, we define $$ f(A) = ( f(a_{ij} ) )_{ n \times n} $$ let $$ A = \begin{bmatrix} \pi /2 - \theta & \theta \\ -\theta & \pi /2 - \theta \end{bmatrix} $$ then,
Correct option is A. Sin A in invertible