试说明代数式x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3的值与字母x、y的取值无关.
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试说明代数式x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²
试说明代数式x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3的值与字母x、y的取值无关.
试说明代数式
x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3
的值与字母x、y的取值无关.
试说明代数式x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3的值与字母x、y的取值无关.
x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3=
=(x³y³-2x³y³+x³y³)+(-1/2x²y+0.5x²y)+(y²+y²-2y²)-3
=-3
x³y³-1/2x²y+y²-2x³y³+0.5x²y+y²+x³y³-2y²-3
=(x^3y^3-2x^3y^3+x^3y^3)+(-1/2x^2y+0.5x^2y)+(y^2+y^2-2y^2)+3
=0+0=0=3=3,所以原式的值与x,y的取值无关。
(^表示乘方)