math problem 01

👨🏻‍🏫 學術台數學

用戶105629

2008-04-02 11:17 pm

http://farm4.static.flickr.com/3279/2382435594_29593acb23_o.jpg

更新1:

can u explain more on the integration........by the way, you integration seens wrong......

更新2:

how do u integrate ∫xsin(x^2) dx ???

回答 (1)

myisland8132

2008-04-03 12:17 am

✔ 最佳答案

∫∫sin(x^2) dxdy
=∫∫sin(x^2)dydx [y from 0 to x][x from 0 to 1]
=∫xsin(x^2) dx [from 0 to 1]
=1/2∫sin(x^2) d(x^2)
=-1/2cos(x^2) [0,1]
=(-1/2)(cos1-1)
=(1/2)(1-cos1)

2008-04-03 11:07:50 補充：
use substitution

d(x^2)=(2x)dx

👍 0 👎 0

收錄日期: 2021-04-26 13:05:26
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080402000051KK01064

檢視 Wayback Machine 備份