作者henry9621205 (清心小子)
看板trans_math
标题[积分] 不定积分
时间Wed May 12 15:09:28 2010
x arcsinx
S----------dx=?
(1+x^2)^2
解答第一行:
-arcsinx 1
--------- +S----------------------dx
2(1+x^2) 2(1+x^2)(1-x^2)^(1/2)
...
...
最後答案是:
-arcsinx 2^(1/2) 2^(1/2) x
--------- + -------- arctan----------------dx + C
2(1+x^2) 4 (1-x^2)^(1/2)
看不懂解答第一行是怎麽变出来的.谢谢!
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◆ From: 203.64.181.187
1F：→ a88241050:分部积分.. 140.135.32.38 05/12 15:10
2F：→ UT5:这题要算很久.. 219.85.184.10 05/12 16:16
3F：推 midarmyman:印象中是微甲来的 我记得我算式写了 140.117.198.78 05/12 16:27
4F：→ midarmyman:半张纸 140.117.198.78 05/12 16:28
5F：→ midarmyman:刚刚算了一下 其实还好 140.117.198.78 05/12 17:04
6F：→ doom8199:#1Biuupdl140.113.141.151 05/12 19:28
7F：→ henry9621205:所以结论是..还是得自己算@@ 203.64.181.194 05/12 19:47
8F：→ henry9621205:我有想到是分部 有开头提示一下? 203.64.181.194 05/12 19:48
9F：推 midarmyman:分部之後 剩下那个积分用三角代换 140.117.198.78 05/12 20:55
10F：→ midarmyman:然後分子分母同除cos^2 140.117.198.78 05/12 20:55
11F：→ henry9621205:感恩..等等试试看!! 203.64.181.189 05/12 21:07