(x-y)^2+7(x+y)-11(x-y)^2-8(x+y),先化简.再求值
3个回答
(x-y)^2+7(x+y)-11(x-y)^2-8(x+y),
=-10(x-y)²-(x+y) 当x+y=-3,x-y=-1时
=-10*(-1)²-(-3)
=-10+3
=-7
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