(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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

2. Relevant equations

θ=(taninverse y/x)

θ'=((1)/((y/x)^2 + 1)))(x(dy/dx))+(y)/(x^2)

3. 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?

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# Homework Help: Rate of Change in theta

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