作者bewilderment (发烧夏天)
看板trans_math
标题[微分] 有绝对值得ln
时间Wed Jan 16 22:46:23 2008
求f(x)=ln|x|在x≠0之导数
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 140.119.196.46
1F：推 bolue:1/x ? 122.121.71.4 01/17 00:22
2F：推 xSAUCEx:1/x? 163.13.147.10 01/17 02:14
3F：推 TaiwanFlight:1/x 218.163.179.11 01/17 09:12
4F：→ zptdaniel:1/x123.194.101.225 01/17 11:10
5F：推 david7834:1/x, for all x except zero. 61.225.194.65 01/17 20:20
6F：推 goshfju:f(x) = lnx for x>0 => f'(x) = 1/x 218.167.72.220 01/19 06:08
7F：→ goshfju:f(x) = ln(-x) for x<0 =>f'(x) = -1/(-x) 218.167.72.220 01/19 06:09
8F：→ goshfju:=1/x 218.167.72.220 01/19 06:10
9F：推 kcuricky:X本来就不能为负吧? 123.192.155.40 01/21 00:38
10F：推 bolue:可以吧? 122.121.72.17 01/23 02:18
11F：推 kevinztw:在x=0不连续...所以导数不存在 59.104.199.223 01/23 15:51
12F：推 kevinztw:x>0的部分导数为 1/x 59.104.199.223 01/23 15:58
13F：→ kevinztw:x<0时导数是 1/x 59.104.199.223 01/23 15:59
14F：推 willie7820:1/X,此结果对於所有不等於零之实数成立218.167.173.137 01/29 11:30