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manhdoan454545
2 năm trước
Cho phương trình:$x^2-(2m+1)x+m-3=0$ (1)(với x là ẩn số) a)Chứng minh rằng phương trình (1) luôn có 2 nghiệm phân biệt $x_1,x_2$ với mọi m b)Với $x_1,x_2$ là hai nghiệm của phương trình (1).Tìm giá trị của m để $x^2_1-x_1+2mx_2-x_1x_2=8$
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