设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项

问题描述:

设m和n均不为0,3x^2y^3和-5x^(2+2m+n)y^3是同类项
求(3m^3-m^2n+3mn^2-6mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)的值
1个回答 分类:数学 2014-10-17

问题解答:

我来补答
根据题意有:
2+2m+n=2
所以
2m+n=0
所以
n=-2m
将n=-2m代入(3m^3-m^2n+3mn^2-6mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)得:
(3m^3-m^2n+3mn^2-6mn^2+9n^3)\(5m^3+3m^2n-6mn^2+9n^3)
=(-65m^3)/(-97m^3)
=65/97
(你的题目分子似乎写错项了,有两个是同类项了)
 
 
展开全文阅读
剩余:2000