推 ijdi301:謝謝大大 可以順便說一下dx怎麼出來? 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
--
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推 ijdi301:太強了 這題用了好多觀念= = 一下轉不過來 61.57.123.180 07/06 16:57
→ ijdi301:謝謝大大 61.57.123.180 07/06 16:57