Here, ux = ucosθ
and uy = usinθ
At maximum height, vy = 0
⇒ u sinθ - gt = 0
⇒ \(t =\frac{usin\theta}{g}\)
So, time of flight (T) = 2t = \(\frac{2u\,sin\theta}{g}\)
and horizontal range = u cosθ × T = \(\frac{u^2\,sin\theta\,cos\theta}{g}=\frac{u^2\,sin2\theta}{g}\)