when the car is x km from the specified point,
tanθ = x/2
so that means that
sec^2θ dθ/dt = 1/2 dx/dt
So now just find secθ when x=1, and plug in your numbers to find dx/dt
A revolving searchlight in a lighthouse 2 km offshore is following a car traveling slowly along the shore. When the car is 1 km from the point on the shore that is closest to the lighthouse, the searchlight is Page 305turning at the rate of 0.25 rev/hr. How fast in kph is the car traveling at this moment?
1 answer