That is close 2

A particle is projected up an inclined plane of base angle $\alpha$ with the horizontal with an initial velocity $V$ . The particle collides elastically with the incline and rebounds vertically . If the particle reaches back the point of projection after time
$\large T = \dfrac {aV}{g \sqrt{1+b\sin^2\alpha}}$ , then enter the value of $a + b$ .

Note : $g$ denotes the acceleration due to gravity.

Assume the inclined plane is fixed to the ground.