先化简,再求值:(xy-x^2)÷x^2-2xy+y^2/xy*x-y/x^2,其中x=2009,y=2010

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先化简,再求值:(xy-x^2)÷x^2-2xy+y^2/xy*x-y/x^2,其中x=2009,y=2010
先化简,再求值:(xy-x^2)÷x^2-2xy+y^2/xy*x-y/x^2,其中x=2009,y=2010

先化简,再求值:(xy-x^2)÷x^2-2xy+y^2/xy*x-y/x^2,其中x=2009,y=2010
(xy-x^2)÷[(x^2-2xy+y^2)/xy]*(x-y)/x^2
=-x(x-y)*[xy/(x-y)^2]*(x-y)/x^2
=-y
y=2010
=-2010