標題:
please help me! Integration
- 20分!!agnes b 野問題
- 統計學問題設A，B為兩獨立事件，證明A，B' 亦為獨立事件 我看答案寫 P(A∩B')=P(A)-P(A∩B)我覺得很奇怪 P(A)和P(B)兩事件外面不是還有一個正方形框框嗎- (加起來等於一)，題目也沒說P(A)和P(B)和是一阿 那為什麼外面那一整塊不見了呢-@1@
- 而家銀行新做既樓宇按揭係 P減幾-@1@
此文章來自奇摩知識+如有不便請留言告知
發問:
please help me integrate step by step. Integrate (R/r)dr where r= (h^2+R^2)^1/2 with boundary from 0 to a. Thanks 更新: sorry, it's dR 更新 2: The answer is correct, but must I use tan@ or sec^2@ to integrate it? Is there any simplier method?
最佳解答:
S (0,a) R/r dR = S (0,a) R/(h^2 + R^2)^1/2 dR Put R = htan@, dR = hsec^2@d@ When R = 0, @ = 0, when R = a, @ = tan^-1(a/h) So, the integral becomes: S (0,tan^-1(a/h) h^2sec^2@tan@/hsec@ d@ = h S (0,tan^-1(a/h) sec@tan@ d@ = h [sec@](0,tan^-1(a/h)) = h[(1/h)sqrt(a^2 + h^2) - 1] = sqrt(a^2 + h^2) - h
其他解答:
這裏可以幫到你 http://actioni.w7.c361.net/yahoo.com.hk/hk/auction/178987536|||||http://img100.imageshack.us/img100/5934/10770502.png|||||Integrate (R/r)dr, 0 to a =R * Integrate (1/r) dr, 0 to a =R * ln r, 0 to a = R( ln a - ln 0) => undefined wrong question? do u meant dR?
留言列表
