作者LuisSantos ( )
看板trans_math
标题Re: [考古] 积分
时间Sun Jul 6 16:52:15 2008
1F:推 ijdi301:谢谢大大 可以顺便说一下dx怎麽出来? 61.57.123.180 07/06 16:48
x
t = tan(---)
2
x -1
--- = tan (t)
2
1 1 2
--- dx = --------- dt => dx = --------- dt
2 1 + t^2 1 + t^2
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 61.66.173.21
2F:推 ijdi301:太强了 这题用了好多观念= = 一下转不过来 61.57.123.180 07/06 16:57
3F:→ ijdi301:谢谢大大 61.57.123.180 07/06 16:57