S cos^2X dx=?
S=積分
微積分(積分) S cos^2X dx
2012-05-28 3:09 pm
回答 (2)
2012-05-28 3:25 pm
✔ 最佳答案
∫Cos^2x dx=(1/2) ∫(1+Ccos2x) dx
=(1/2) ∫1dx+(1/2) ∫Ccos2xdx
=(1/2) ∫1dx+(1/4) ∫Ccos2xd(2x)
=(1/2) ∫1dx+(1/4) ∫Ccos2xd(2x)
=x/2+Sin2x/4+c
2012-05-28 3:29 pm
cos 2x = 2cos^2 x -1
cos^2 x = (1/2)(1+ cos 2x)
∫ cos^2 x dx
= (1/2) ∫ (1+ cos 2x) dx
= (1/2) (x+ (1/2)sin 2x) +C
= (1/4) (2x + sin 2x) +C
cos^2 x = (1/2)(1+ cos 2x)
∫ cos^2 x dx
= (1/2) ∫ (1+ cos 2x) dx
= (1/2) (x+ (1/2)sin 2x) +C
= (1/4) (2x + sin 2x) +C
收錄日期: 2021-04-30 16:43:47
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120528000010KK01116