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candycute
2 năm trước
Cho tam giác ABC vuông tại A.Tia phân giác góc C cắt AB tại E.Trên cạnh BC lấy điểm D sao cho CD=CA a. Chứng minh tam giác CAE=CDE b.Chứng minh CE là đường trung trực AD c.Tia DE cắt CA tại K. Chứng minh CK=BC d.Tìm điều kiện của tam giác ABC để BK=2AK
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