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Vushun2000
2 năm trước
Cho Δ ABC(AB=AC) và i là trung điểm của đáy BC. Dựng tia Cx song song với tia BA sao cho hai tia BA và Cx nằm trong hai nữa mặt phẳng đối nhau có bờ là đường thẳng BC.Lấy một điểm D nào đó trên AB.Gọi E một điểm nằm trên tia Cx sao cho BD=CA a, chứng minh ΔBID =ΔCIE. b, chứng Minh rằng 3 điểm D, I, E thẳng hàng ,,,,,,,,,,,,và hình vẽ
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