First simplify, then evaluate: (xy-3x ^ 2) - 2 (xy-2x ^ 2-1), where x and y satisfy the condition x + 2 + (Y-1) ^ 2 = 0
X + 2 + (Y-1) ^ 2 = 0
X + 2 = 0, (Y-1) ^ 2 = 0
x+2=0,y-1=0
x=-2,y=1
therefore
(xy-3x^2)-2(xy-2x^2-1)
=(xy-3x^2)-2xy+4x^2+2
=-xy+x^2+2
=-(-2)×1+(-2)^2+2
=2+4+2
=8
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