问题描述: 已知m-n=3,mn=-3,求(-m-4n-mn)-(2mn-2m-3n)-(3mn+2n-2m)的值 1个回答 分类:数学 2014-10-23 问题解答: 我来补答 (-m-4n-mn)-(2mn-2m-3n)-(3mn+2n-2m)=-m-4n-mn-2mn+2m+3n-3mn-2n+2m=-m+2m+2m-4n+3n-2n-mn-2mn-3mn=3m-3n-6mn=3(m-n)-6mn=3*3-6*(-3)=9+18=27 展开全文阅读