integration

2015-07-03 8:16 pm
How to integrate:

-x lnx dx

Please explain it step by step.

回答 (2)

2015-07-03 8:49 pm
✔ 最佳答案
Integration By Parts:
∫udv = uv - ∫vdu

∫-x ln x dx
=-∫ln x d(x²/2)
=-x² (ln x) /2 - [-∫x²/2 d(lnx)]
=-x² (ln x) /2 + ∫x²/2 (1/x)dx
=-x² (ln x) /2 + ∫x/2 dx=-x² (ln x) /2 + x²/(2*2) + C
=-x² (ln x) /2 + x²/4 + C







2015-07-03 13:51:54 補充:
抱歉 ...
原來你係到回答緊 0.0

2015-07-03 14:49:13 補充:
黑色字就2行至第4行係用緊 Integration By Parts

2015-07-03 15:09:48 補充:
也可以看看 知足常樂 ( 知識長 ) 在意見區的回答
2015-07-03 8:52 pm
又撞題了...
那我暫時不答了~

我做了在以下的連結:
http://postimg.org/image/bxab0jyvh/

2015-07-03 15:00:22 補充:
無事~
唔駛擔心~

你繼續答啦~
我而家唔得閒住~ =P


收錄日期: 2021-04-18 14:31:46
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