The law of motion of a material point has the form r = aCos (n / 2t) i bsin (2пt) j, where a = 2 m, b = 0.5 m. Find the value of the velocity vector of the point at time 1 s.

Detailed solution with a short recording of the conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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