Question 554826
two boats leave the same port at the same time, the first boat heads due north at 15 knots and the other due west at 12 knots, after 2 hours, how fast is the distance between the boats increasing?
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Their relative speed, the speed of either wrt the other, = {{{sqrt(15^2 + 12^2) = sqrt(369)}}} knots
It's constant, doesn't vary with distance.