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arohalove303261
2 năm trước
Cho biểu thức A=2x²(x+y)-2 a) Tính giá trị của biểu thức A biết x=2-y, y=1 b) Tính giá trị của biểu thức A biết x=-y c)Tính giá trị của biểu thức A biết x=4y và x-2y=2
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