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Rayquesto
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Homework Statement
Ship A is traveling due West towards a lighthouse at a speed of 15km/hr. Ship B is traveling due north away from the lighthouse at a speed of 10 km/hr. Let x be the distance between ship A and the lighthouse at time t, and let y be the distance between ship B and the light house at time t.
Since I cannot show a picture, the lighthouse is directly below ship B which is headed north (So, the light house is south of ship B) and ship A is directly east of the lighthouse headed toward the lighthouse to directly west.
a)I figured this one out. It wasn't that bad to me.
b) Let θ be the angle in reference to ship A between ship B and the lighthouse. Find the rate of change of θ, in radians per hour, when x=4km and y=3km
Homework Equations
θ=(taninverse y/x)
θ'=((1)/((y/x)^2 + 1)))(x(dy/dx))+(y)/(x^2)
The Attempt at a Solution
θ'=((1)/((3km/4km)^2 +1)))(4km(dy/dx))+(3km)/(4km^2)
but how would you find dy/dx
do I assume it is y/x?