1. The problem statement, all variables and given/known data A projectile's horizontal range on level ground is R =v0^2 sin2(theta)/g. At what launch angle or angles will the projectile land at half of its maximum possible range. 3. The attempt at a solution So what i did was: Half the range occurs when sin(2θ) = 0.5 So 2θ = arcsin(0.5)...so θ = 0.5*arcsin(0.5) = 15 (degrees) but when i enter that in it says there is more than one answer, how do i get the other answer?