積分 之 湊微分 & 分部微分
積分x lnx dx
超簡單微積分(急)!!!要求詳解
2011-01-25 6:12 am
回答 (2)
2011-01-25 6:26 am
✔ 最佳答案
int x ln x dx= int ln x d(x^2/2)
=(x^2/2) ln x - int (x^2/2) d( ln x)
=(x^2/2) ln x - int (x^2/2) (1/x) dx
=(x^2/2) ln x - int (x/2) dx
=(x^2/2) ln x - (x^2/4) +C
2011-01-25 6:27 am
∫ x lnx dx
= (1/2) ∫ lnx d(x^2)
= (x^2/2)ln(x) - (1/2) ∫ (x^2)(1/x) dx
= (x^2/2)ln(x) - x^2/4 + C
= (1/2) ∫ lnx d(x^2)
= (x^2/2)ln(x) - (1/2) ∫ (x^2)(1/x) dx
= (x^2/2)ln(x) - x^2/4 + C
收錄日期: 2021-04-26 14:05:26
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