先将代数式(x-x+1/x)÷(1+x²-1/1)化简,再在-1,0,1,2中选取一个合适的数X带入求值

问题描述:

先将代数式(x-x+1/x)÷(1+x²-1/1)化简,再在-1,0,1,2中选取一个合适的数X带入求值
1个回答 分类:数学 2014-09-26

问题解答:

我来补答
(x-x+1/x)÷(1+x²-1/1)
=[(x+1)/(x²+x-x)]÷[(x²-1)/(x²-1+1)]
=[(x+1)/(x²)]÷[(x²-1)/(x²)]
=[(x+1)/(x²)]*[(x²)/(x-1)(x+1)]
=x-1
当x=2时
上式=1
 
 
展开全文阅读
剩余:2000