|(5n/n+1)-5|

题目

|(5n/n+1)-5|
n属于正整数

答案

5n/(n+1)--5=5[n/(n+1)-1]=5[n-(n+1)/(n+1)=-5/(n+1)
|5n/(n+1)-5||-5/(n+1)|1/|n+1||n+1|>5/0.001=5000
---n4999.