作者Honor1984 (希望願望成真)
看板Grad-ProbAsk
標題Re: [理工] 求此積分過程
時間Fri Aug 9 00:17:14 2013
※ 引述《xoo1208 (RaInBoW)》之銘言:
: https://www.dropbox.com/s/zl7062b5u63iheu/Questions2.jpg
: 求此積分過程 ~~
exp(∫(1-x^2)^(-1) d(1-x^2))
= x∫-------------------------------- dx
x^2
1
= x∫ -------------- dx
x^2 (1-x^2)
1/(x^2(1-x^2)) = 1/x^2 + 1/(1-x^2)
= 1/x^2 + (1/2)[1/(1-x) + 1/(1+x)]
= x [(-1/x) + (1/2)ln[(x+1)/(1-x)]]
= -1 + (x/2)ln[(x+1)/(1-x)]
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 128.220.159.5
推 xoo1208:exp裡面是先用變數變換代換嗎 ? 08/09 00:21
→ Honor1984:對 08/09 00:35
→ xoo1208:謝謝大大~~ 08/09 00:39