化简求值 2(x²y+xy²)+2(x²y-1)-2xy²-2,其中x=-2,y=2

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化简求值 2(x²y+xy²)+2(x²y-1)-2xy²-2,其中x=-2,y=2

化简求值 2(x²y+xy²)+2(x²y-1)-2xy²-2,其中x=-2,y=2
化简求值 2(x²y+xy²)+2(x²y-1)-2xy²-2,其中x=-2,y=2

化简求值 2(x²y+xy²)+2(x²y-1)-2xy²-2,其中x=-2,y=2
x+y=0
2(x²y+xy²)+2(x²y-1)-2xy²-2
=2xy(x+y)+2xy(x-y)-4
=2xy(x-y)-4
=2*2*(-2)*(-4)-4
=28

2(x²y+xy²)+2(x²y-1)-2xy²-2
=4x^2y-4
=4*(-2)^2*2-4
=32-4
=28

2(x²y+xy²)+2(x²y-1)-2xy²-2
=2x²y+2xy²+2x²y-2-2xy²-2
=4x²y-4
=4×(-2)²×2-4
=32-4
=28