已知|x+2|+(y-1/2)^2=0,求代数式2x^2y-2[xy^2-3(xy^2-2x^2

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/09/01 10:15:49

已知|x+2|+(y-1/2)^2=0,求代数式2x^2y-2[xy^2-3(xy^2-2x^2
+1)]的值

∵|x+2|+(y-1/2)²=0
∴x+2=0、y-1/2=0
x=-2、y=1/2
2x²y-2[xy²-3(xy²-2x²+1)]
=2x²y-2[xy²-3xy²+6x²-3]
=2x²y-2xy²+6xy²-12x²+6
=2x²y+4xy²-12x²+6
=2×(-2)²×1/2+4×(-2)×(1/2)²-12×(-2)²+6
=4-2-48+6
=-40

已知xy/x+y=3,求代数式2x-5xy+2y/x-3xy+y 已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值已知xy/x+y=2,求代数式3x-xy+3y/-x+3xy-y的值已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值已知x+y=-1,xy=-2,求代数式-5（x+y)+(x-y)+x(xy+y)的值已知x+y=3,xy=2求代数式 -x的平方y-xy平方已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 已知y=3+xy,求代数式2x+3xy-2y/x-2xy-y的值. 已知x+y=-1,xy=-2,求代数式-5（x+y)+(x-y)+2(xy+y)的值已知xy/x+y=2,求代数式3x-5y+3y/-x+3xy-y 已知X+Y=-1,xy=-2,求代数式-5(x+y)+(x-y)+(xy+y)的值已知:x-xy=40,xy-y=-20,求代数式x-y和x+y-2xy的值.