求证:1⼀ln2+1⼀ln3+1⼀ln4+……+1⼀lnn>1⼀2

2025-03-20 12:39:07
推荐回答(1个)
回答1:

n>1,lnn>0,
所以1/lnn>0,各项为正
1<201/ln2>1>1/2,其他各项为正
1/ln2+1/ln3+1/ln4+……+1/lnn>1/2