[6] 3. Let
r(t)be the position of a projectile which is launched from the point
(0,0,2)meters at
t=0sec with initial velocity
(:50,60,80:)(m)/(sec). Assuming the projectile is influenced only by gravity, and that the acceleration due to gravity is
9.8(m)/(sec^(2)), we have
r^('')(t)=(:0,0,-9.8:)(m)/(sec^(2)). Find the position function
r(t), and the time at which the projectile will hit the
xyplane (i.e. the ground), to the nearest 0.01 second.