Asked by Hailey

An airplane flys at a constant altitude of 2 miles and a constant speed of 600 miles per hour on a straight course that will take it directly over a kangaroo on the ground. How fast is the angle of elevation of the kangaroo's line of sight increasing when the distance from the kangaroo to the plane is 3 miles? Give your answer in radians per minute.
Answered by Reiny
Why are you posting this again ?
I answered your same question about 3 hours ago.
Always check back on your posts, mark their time, and they are easy to find that way.
http://www.jiskha.com/display.cgi?id=1412721979
Answered by Hailey
The answer was wrong!
Answered by Reiny
Did you try to find an error in my solution?
How do you know it is wrong?
Answered by Steve
The math looks good to me, but the negative answer is strange because the question was, how fast is the angle increasing?

That is because dx/dt = -600; the plane is approaching the kangaroo.

Hailey, did you do as Reiny asked, and check his math?
Answered by Reiny
Yup, Steve is right, I had the plane flying away from the kangaroo, should have read it more carefully.
The numerical answer would simply change to a positive rate of change of the angle.
Answered by Lindsay
This answer is still incorrect. The 3 miles from the airplane to the kangaroo is the hypotenuse of the triangle. It is the shortest distance from the airplane to the kangaroo, not the horizontal distance.
There are no AI answers yet. The ability to request AI answers is coming soon!