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nhinhinhitruongtruongthptqvp
2 năm trước
Cho tam giác ABC vuông tại A có:AB=3cm,AC=4cm, kẻ đường cao AH. a)Chứng mình tam giác ABC và tam giác HBA đồng dạng với nhau b) Tính độ dài các cạnh BC.AH c) Chứng minh AC²=AH.BC d) Phân giác của góc ACB cắt AH tại AE, cắt AB tại D. Tính tỉ số diện tích của 2 tam giác ACD và HCE (Làm phần d thui cũng được ạ Camon😚)
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