[理工] [工數]-ODE
看板Grad-ProbAsk作者fonlintw0621 (fonlintw0621)時間15年前 (2010/03/24 13:14)推噓5(5推 0噓 4→)留言9則, 5人參與討論串212/280 (看更多)
2
y'''' + 16 y = t + 1
y
xy' - y = ------------- y(2) = 2 已解決
ln y - ln x
y/x
y' - y/x = ----------
ln(y/x)
let y = ux
u
u + x du/dx - u = ----------
ln u
( ln u ) / u du = 1/x dx
2
0.5 (ln u) = ln x + c
2
0.5(ln y/x) = ln x + c
--
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◆ From: 140.118.33.168
推
03/24 13:21, , 1F
03/24 13:21, 1F
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03/24 13:21, , 2F
03/24 13:21, 2F
→
03/24 13:29, , 3F
03/24 13:29, 3F
推
03/24 13:31, , 4F
03/24 13:31, 4F
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03/24 13:36, , 5F
03/24 13:36, 5F
推
03/24 13:38, , 6F
03/24 13:38, 6F
※ 編輯: fonlintw0621 來自: 140.118.33.168 (03/24 13:44)
→
03/24 14:01, , 7F
03/24 14:01, 7F
推
03/24 14:02, , 8F
03/24 14:02, 8F
推
03/25 09:56, , 9F
03/25 09:56, 9F
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