A plane flying with a constant speed of 29 \(\frac{km}{min} \) passes over a ground radar station at an altitude of 7 km and climbs at an angle of 40 degrees. What is the distance between the radar station and the plane after 4 minutes? At what rate is the distance from the plane to the radar station increasing 4 minutes later?
x distance from the station = s * t cos 40 s = speed ( in km/min) t = time (in miutes)
y distance from the station = 7 + s*t sin 40
Using distance formula :
d2 = (s t cos 40)2 + (7 + s t sin 40 )2 Given: s t = 29 * 4 = 116 <===== subst. in and solve for d
Take the derivative with respect to 't' to find out how fast it is changing at t= 4 <====== can you do that?