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minhsonz5555
2 năm trước
Bài 5: Cho tam giác ABC vuông cân tại A. P là điểm di chuyển trên cạnh AB. Từ P kẻ đường thẳng song song với AC, cắt BC tại M. Gọi Q là hình chiếu của M trên AC. a) Tứ giác APMQ là hình gì? Vì sao? b) Tìm vị trí của điểm P trên cạnh AB để tứ giác APMQ là hình vuông. c) Gọi O là trung điểm của PQ. Chứng minh rằng khi P di chuyển trên cạnh AB thì O di chuyển trên một đoạn thẳng cố định
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