A body is projected from the ground with a velocity u at an angle θ with the horizontal. The average velocity of the body between its point of projection and the highest point of its trajectory is

A is the highest point on the trajectory. Average velocity = displacement OA time taken =hmax2+R2412tf    ......... (1)Where hmax=u2sin2⁡θ2gR=u2sin2θg, and  tf=2u sin ⁡θgUsing these in Eq. (1) and simplifying, we get Average velocity =u21+3 cos2 ⁡θ1/2