先化简,再求值.
问题描述:
先化简,再求值.
[(2/x+1)+(4/x方-1)]÷x/x-1
x=2、
答
[2/(x+1)+4/(x²-1)]÷x/(x-1)=[(2/(x+1)+4/(x-1)(x+1)]÷x/(x-1)=[2(x-1)/(x+1)(x-1)+4/(x-1)(x+1)]÷x/(x-1)=[2(x-1)+4/(x-1)(x+1)]÷x/(x-1)=[2(x+1)/(x-1)(x+1)]÷x/(x-1...