Trong mặt phẳng (Oxy), chất điểm chuyển động với phương trình: x=7-8sin(4πt); y=3+8sin(4πt) Xác định vị trí của chất điểm lúc t = 1s. Xác định dạng của đạo. Xác định vector vận tốc và tính độ lớn vận tốc tại t = 2 s. Xác định vector gia tốc và tính độ lớn gia tốc tại t = 3 s.

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