Integation by Parts
回答 (2)
2007-01-04 9:54 pm
✔ 最佳答案
∫x^2 Inx dx = ∫(x^2)( Inx) dx
= ∫Inx d (x^3)/3
= Inx (x^3)/3 - ∫(x^3)/3 d(Inx)
= Inx (x^3)/3 - ∫(x^3)/3*(1/x) dx
= Inx (x^3)/3 - ∫(x^2)/3 dx
= Inx (x^3)/3 - (x^3)/9 + C ,where C is a constant
2007-01-04 12:18 pm
∫x^2 Inx dx
=1/3∫ Inx dx^3
= 1/3 (Inx) x^3-1/3∫ x^3 (1/x) dx
=1/3 (Inx) x^3-1/3∫ x^2 dx
=1/3 (Inx) x^3-1/9* x^3
2007-01-04 04:21:26 補充：
我用software做完結果一樣﹐應該冇錯
=1/3∫ Inx dx^3
= 1/3 (Inx) x^3-1/3∫ x^3 (1/x) dx
=1/3 (Inx) x^3-1/3∫ x^2 dx
=1/3 (Inx) x^3-1/9* x^3
2007-01-04 04:21:26 補充：
我用software做完結果一樣﹐應該冇錯
收錄日期: 2021-04-25 16:50:12
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