- #1

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## Homework Statement

Two ships A and B move with constants speeds 48 km/h and 60 km/h respectively. At a certain instant ship B is 30 km west of A and is travelling due south. Find:

i) The direction ship A should steer in order to get a close as possible to ship B.

## Homework Equations

V

_{ab}= V

_{a}- V

_{b}

## The Attempt at a Solution

Well, V

_{b}= 0i - 60j

V

_{a}= -48cosxi - 48sinxj

and therefore

V

_{ab}= -48cosxi + (60 - 48sinx)j

I have drawn diagrams to help but I can't figure out the right angle. I tried differentiation to find the lowest possible value for j (they are already horizontally across from each other) but I got 1 for an answer which I know is not correct. Any advice.