用歸納法證明
n=2時,1+1/3>√5/2成立
設(shè)n=k時：
(1+1/3)(1+1/5)(1+1/7)…(1+1/(2k—1))＞√(2k+1)/2成立
則n=k+1時
(1+1/3)(1+1/5)(1+1/7)…(1+1/(2k—1))(1+1/(2k+1))
>(1+1/(2k+1))*√(2k+1)/2
>1/2*[√(2k+1)+1/√(2k+1)]
=1/2*√[2k+1+2+1/(2k+1)]
>√(2k+3)/2
也成立,故對n＞1,n屬于正整數(shù)都成立