問題詳情

2. An experiment detects that a particle at (1,0) (on the xy-plane) is moving towards the north at thespeed 3 meters per minute. At the same time another particle at (-2,1) is moving towards the eastat the speed 4 meters per minute.
【題組】

(a) (5%) Let s(t) be the distance (in meters) between the two particles in t minutes. s(t)=_____

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