一道数学题！！！！
已知xy=-2,x-y=3,求(x+y)(x-y)-y^2+(x-y)^2-（6x^2 y-2xy^2)÷2y的值
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2023年05月25日 05:15
热门回答（2个）
游客1
(x+y)(x-y)-y^2+(x-y)^2-（6x^2 y-2xy^2)÷2y
=x^2-y^2-y^2+x^2-2xy+y^2-(3x^2-xy)
=-(x^2+y^2+xy)
=-(x-y)^2-3xy
=-9+6
=-3
游客2
(x+y)(x-y)-y^2+(x-y)^2-（竖迟坦旦轿6x^2 y-2xy^2)÷2y
=x^2-y^2-y^2+x^2-2xy+y^2-2y（3x^2 -xy)÷2y
=2x^2-y^2-2xy-（余桐3x^2 -xy)
=-x^2-y^2-xy
=-(x-y)^2-2xy-xy
=-(x-y)^2-3xy
=-3^2-3*(-2)
-3
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