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nhanpham263
2 năm trước
cho tam giác abc vuông tại a . đường cao ah . gọi i,k lần lượt là hình chiếu của h lên ab và ac a) chứng minh aihk là hình chữ nhật b) chúng minh ah^2b=bh*ch c) chứng minh tam giác aik đồng dạng với tam giác acb d) tính diện tích tam giác aik, biết bc=10cm , ah=4cm
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