Question 996070
R(theta) = (v0^2/g)*sin(2*theta)
R ' (theta) = (v0^2/g)*2*cos(2*theta)
0 = (v0^2/g)*2*cos(2*theta)
cos(2*theta) = 0
2*theta = arccos(0)
2*theta = pi/2 + 2pi*n or 2*theta = -pi/2 + 2pi*n
theta = pi/4 + pi*n or theta = -pi/4 + 2pi*n


Ignore the theta = -pi/4 + 2pi*n portion since the first part is negative pushing it out of the interval [0,pi/2]


Only one value of n will make theta = pi/4 + pi*n in the interval [0,pi/2]. This value of n is n = 0


If n = 0, then theta = pi/4


Final Answer: <font color="red">pi/4 = 0.78539816339744</font> (decimal value is approximate)


pi/4 radians = 45 degrees
This is halfway between 0 and 90 degrees