题目内容 (请给出正确答案)
提问人:网友l******8 发布时间:2022年3月13日 12:56
[单项选择题]

速度向量v=sinti+2costj(0<t<2π)与其加速度向量a正交的时间点t是()

A.t=π/4,π/2,2π/3

B.(0,2π)中任一时刻

C.t=π/2,π,3π/2

D.t=π/4,π,3π/4

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