计算(2X^3-3X^2Y-2XY^2)-(x^3-2xy^2+y^3)+(-x^3+3x^2y-y^3)的值,其中,x=1/2,y=1

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计算(2X^3-3X^2Y-2XY^2)-(x^3-2xy^2+y^3)+(-x^3+3x^2y-y^3)的值,其中,x=1/2,y=1
计算(2X^3-3X^2Y-2XY^2)-(x^3-2xy^2+y^3)+(-x^3+3x^2y-y^3)的值,其中,x=1/2,y=1

计算(2X^3-3X^2Y-2XY^2)-(x^3-2xy^2+y^3)+(-x^3+3x^2y-y^3)的值,其中,x=1/2,y=1
(2X^3-3X^2Y-2XY^2)-(x^3-2xy^2+y^3)+(-x^3+3x^2y-y^3)
=2x^3-3X^2Y-2XY^2-X^3+2XY^2-Y^3-X^3+3X^2Y-Y^3
=2x^3-X^3-X^3-3X^2Y+3X^2Y-2XY^2+2XY^2-Y^3-Y^3
=-2Y^3
=-2×(1)^3
=-2

=2x³-3x²y-2xy²-x³+2xy²-y³-x³+3x²y-y³
=-2y³
以x=1/2、y=1代入,得:
原式=-2