I'm studying for an exam and this is one of the sample questions which I cannot figure out. 1. The problem statement, all variables and given/known data 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. 2. Relevant equations Vab = Va - Vb 3. The attempt at a solution Well, Vb = 0i - 60j Va = -48cosxi - 48sinxj and therefore Vab = -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.