Re: [微分] 問一題微分方程式

看板trans_math作者dunerx0712 (orz)時間21年前 (2005/01/05 10:07)推噓2(2推 0噓 1→)

留言3則, 2人參與討論串2/2 (看更多)

※ 引述《artaniss (羽)》之銘言： : R=(ln I-lnIo)/ln10 : Assume that Io=1 : (a)Find the intensity of the 1906 San Francisco Earthquake.(R=8.3) : (b)Find the factor by which the intensity is increased if the Richter : scale measurement is doubled. : (c)Find dR/dI. : 小弟不才,懇請各位前輩賜教 : 謝謝<(_ _)> (a) Io = 1, R = 8.3代入,得 8.3 =( ln I - ln 1) / ln 10 ==> 8.3 * ln 10 = ln I 8.3 8.3 ln 10 = ln I ===> I = 10 =199,526,231.5 ........Ans## (b) Io = 1 R = ln I- ln 1/ ln 10...........(1) 2R = ln I'- ln 1 / ln 10 ........(2) 2 ===> (1)/(2) 得 1/2 = ln I / ln I'==> ln I'= 2 ln I ==> ln I' = ln I ====>兩邊取exp , 得 2 I' = I ............Ans## (c) 兩邊對 I做微分,其餘視為常數 dR/dI = ( 1/ I - 0 )/ ln 10 = 1/ ln 10 *I .........Ans## 題目不難,只是要把觀念弄清楚補比較重要,加油吧..............^^.... -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.114.212.82

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artaniss

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dunerx0712

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dunerx0712

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