Задача 40966.

The material point oscillates according to the law x (t) = A cos (wt + f), where A = 4 cm, w = 50 rad / s, f =? / 4 rad. Calculate the displacement of the point x (t1), its velocity V (t1) and acceleration a (t1) at the moment of time t1 = 0.02 s.

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