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关于x,y的多项式6mx²+4nxy+2x+2xy-x²+y+4不含二次项,

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/27 18:25:46
关于x,y的多项式6mx²+4nxy+2x+2xy-x²+y+4不含二次项,
求多项式2m²n+10m-4n2+2m²n+4m+2n的值
6mx²+4nxy+2x+2xy-x²+y+4
=(6m-1)x²+(4n+2)xy+2x+y+4
6m-1=0
m=1/6
4n+2=0
n=-1/2
2m²n+10m-4n2+2m²n+4m+2n
=4m²+14m-4n²+2n
=4x(1/6)²+14x1/6-4x(-1/2)²-2x1/2
=1/9+7/3-1-1
=1/9+1/3
=4/9
再问: 题抄错了-_-。sorry! 是2m²n+10m-4n+2-2m²n-4m+2n
再答: 2m²n+10m-4n+2-2m²n-4m+2n =6m-2n+2 =6x1/6+2x1/2+2 =1+1+2 =4
再问: 不对吧?
再答: 对的