The vertical displacement (y in metre) of a projectile in terms of its horizontal displacement (x in metre) is given by $y=(\sqrt{3}x - 0.2x^2)$. The time of flight of the projectile is (Acceleration due to gravity = 10 ms$^{-2}$)
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The equation of a projectile's trajectory, $y = (\tan\theta)x - \frac{g}{2u^2\cos^2\theta}x^2$, is a powerful tool. By comparing a given equation to this standard form, you can quickly extract the launch angle $\theta$ and initial speed $u$.