先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2)]÷xy,其中x=10,y=-1/25

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先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2)]÷xy,其中x=10,y=-1/25先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2

先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2)]÷xy,其中x=10,y=-1/25
先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2)]÷xy,其中x=10,y=-1/25

先化简,再求值:[(xy+2)(xy-2)-2(x²y²-2)]÷xy,其中x=10,y=-1/25
[xy²-4-2x²y²+4]/xy
=[xy²-2x²y²]/xy
=xy-2xy
=-xy
当x=10,y=-1/25时
原式=-(10*-1/25)
=2/5

[(xy+2)(xy-2)-2(x²y²-2)]÷xy
=[x^2y^2-4-2x^2y^2+4]/(xy)
=-x^2y^2/(xy)
=-xy
=-10*(-1/25)
=2/5
,其中x=10,y=-1/25