We must find dy/dt given x=10,
Plug in your knowns and you're all set.
A rocket, R, rises vertically from a point A on ground level. It is observed from another point B on the ground, where B is 10 km from A. When the angle of elevation has the value pi/4 radians, this angle is increasing at the rate of 0.005 radians per second. Find, in m/s, the velocity of the rocket at that instant.
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