问题描述: (1/x-3)-(1/x^2-9)-(1/6+2x) 1个回答 分类:数学 2014-11-15 问题解答: 我来补答 应该是1/(x-3)-1/(x^2-9)-1/(6+2x) 1/(x-3)-1/(x^2-9)-1/(6+2x)=1/(x-3)-1/[(x+3)(x-3)]-1/[2(x+3)]=2(x+3)/[2(x-3)(x+3)]-2/[2(x+3)(x-3)]-(x-3)/[3(x+3)(x-3)]=[2(x+3)-2-(x-3)]/[2(x+3)(x-3)]=[x+7]/[2(x+3)(x-3)]=(x+7)/[2(x^2-9)] 展开全文阅读