Question

The range of projectile is 4 times of the height of projectile at an angle of?

A. 75

B. 76

C. 60

D. 90

Answer 1

$$R=4H_{\max}$$

$$\frac{2v_0^2\sin\theta\cos\theta}{g}=4*\frac{v_0^2\sin^2\theta}{2g}$$

$$\tan\theta=1$$

$$\theta=45^\circ$$