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hathuhiendoanthidiem
2 năm trước
Cho tam giác ABC vuông góc tại đỉnh A. Biết AB = c, AC = b, b > c. Kẻ trung tuyến AM và trung tuyến BN. Tìm một hệ thức liên hệ giữa b và c để có AM vuông góc với BN
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