先化简,再求值:[4(xy-1)^2-(xy+2)(2-xy)]÷(1/4xy),其中x=-2 y=1/4

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先化简,再求值:[4(xy-1)^2-(xy+2)(2-xy)]÷(1/4xy),其中x=-2 y=1/4

先化简,再求值:[4(xy-1)^2-(xy+2)(2-xy)]÷(1/4xy),其中x=-2 y=1/4
先化简,再求值:[4(xy-1)^2-(xy+2)(2-xy)]÷(1/4xy),其中x=-2 y=1/4

先化简,再求值:[4(xy-1)^2-(xy+2)(2-xy)]÷(1/4xy),其中x=-2 y=1/4
原式=(4x²y²-8xy+4-4+x²y²)÷(1/4xy)
=(5x²y²-8xy)÷(1/4xy)
=20xy-32
=20*(-2)*(1/4)-32
=-10-32
=-42