Asked by Meghan
A road running north to south crosses a road going east to west at the point P. Car A is driving north along the first road, and an airplane is flying east above the second road. At a particular time the car is 15 kilometers to the north of P and traveling at 55 km/hr, while the airplane is flying at speed 175 km/hr 10 kilometers east of P at an altitude of 2 km. How fast is the distance between the car and the airplane changing?
Would you use the derivative of the pathagorium theorem? How would you go about doing this?
Would you use the derivative of the pathagorium theorem? How would you go about doing this?
Answers
Answered by
scott
D^2 = Pn^2 + Pe^2 + 2^2
use implicit differentiation ... 2 D dD/dt = 2 Pn dPn/dt + 2 Pe dPe/dt
√(15^2 + 10^2 + 2^2) dD/dt = 15 * 55 + 10 * 175
use implicit differentiation ... 2 D dD/dt = 2 Pn dPn/dt + 2 Pe dPe/dt
√(15^2 + 10^2 + 2^2) dD/dt = 15 * 55 + 10 * 175
Answered by
Meghan
But when I did this, I got 141.96 which according to the database I'm entering this into, Is still incorrect.
Answered by
scott
141.96 may have too many significant figures
try rounding to three digits
try rounding to three digits