作者LuisSantos ( )
看板trans_math
标题Re: [考古] 97台大商研(极限)
时间Tue Jul 8 00:21:27 2008
※ 引述《evelynsue (Evelyn)》之铭言：
: _____
: l i m √n^2+n - n = ?
: n →∞
lim √(n^2 + n) - n
n→∞
(√(n^2 + n) - n)(√(n^2 + n) + n)
= lim ----------------------------------
n→∞ √(n^2 + n) + n
(n^2 + n) - n^2
= lim -------------------
n→∞ √(n^2 + n) + n
n
= lim -----------------
n→∞ √(n^2 + n) + n
1 1 1
= lim ------------------- = ------- = ---
n→∞ √(1 + (1/n)) + 1 1 + 1 2
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 61.66.173.21
1F：推 applexgreen:酷118.168.167.235 07/08 00:47
2F：→ evelynsue:酷毙了 123.192.65.88 07/08 19:03