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gianghuong28721
2 năm trước
Cho hình bình hành ABCD tâm O. Gọi P, Q, R lần lượt là trung điểm AB, BC, AD. Lấy 8 điểm trên làm điểm gốc hoặc điểm ngọn các vec tơ. Mệnh đề sai là A. Có 2 vec tơ bằng PQ→ B. Có 4 vec tơ bằng AR→ C. Có 3 vec tơ bằng BO→ D. Có 5 vec tơ bằng OP→ (kèm giải thích)
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