问题描述: (1+2x-4/x²-x-2)÷x+3/x²-1 先化简再求值 X=根号3 1个回答 分类:数学 2014-10-21 问题解答: 我来补答 1+(2x-4)/(x^2-a-2)]/[(x+3)/(x^2-1)]={1+2(x-2)/[(x-2)(x+1)]}(x^2-1)/(x+3)=[1+2/(x+1)](x+1)(x-1)/(x+3)=[x+1+2](x-1)/(x+3)=x-1x=√3 (根3)原式=√3-1. 展开全文阅读