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lloocc2001
2 năm trước
Cho pt: x^2 -(2m+3)x + 4m + 2 = 0 a) CM: pt luôn có nghiệm x1, x2 với mọi m b) tìm m thỏa mãn biểu thức: x1.x2 - x1^2 - x2^2 = 17
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