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khatram2009
2 năm trước
Cho phương trình x - (n+1)x+ 2n– 2 =0 (1) (với n là tham số). a) Giải phương trình (1) khi n= 2. b) Tìm giá trị của n để phương trình (1) có hai nghiệm x1,x2 thỏa mãn 3(x1+x2)-x1x2=10
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