derivatives-x^(x^x)

2011-10-16 7:25 pm
f(x)=x^(x^x)=y
In(y)=x^x.In(x)
In(In(y))=In(x^x.In(x))
In(In(y))=x.In(x)+In (In(x))......(1)
Method 1
Using chain rules:
dy/dx.1/In(y).1/y=(x.1/x+1.In(x))+In(x)/x.1/x .....(2)
dy/dx=In(y).y(1+In(x)+In(x)/(x^2))
dy/dx=x^x.In(x).x^(x^x)(1+In(x)+In(x)/(x^2))
Method 2
In(In(y))=x.In(x)+In (In(x))
y=f(x)=e^{e^[x.In(x)+In (In(x))]} ->f(g(u(x)))
dy/dx= f'(g(u(x)))+g'(u(x))+u'(x)=
e^{e^[x.In(x)+In (In(x))]}+e^[x.In(x)+In (In(x))]+d/dx x.In(x)+In(In(x))
using(2):
e^{e^[x.In(x)+In (In(x))]}+e^[x.In(x)+In (In(x))]+(x.1/x+1.In(x))+In(x)/x.1/x
e^{e^[x.In(x)+In (In(x))]}+e^[x.In(x)+In (In(x))]+(1+In(x)+In(x)/(x^2))
Method 3
A bit similar to method 1
See:http://www.youtube.com/watch?v=N5kkwVoAtkc&feature=player_embedded#!
dy/dx=x^(x^x)[x^x(In(x)+1)In(x)+x(x-1)]

Damn, they drive me nuts, please help!!!
更新1:

http://www.youtube.com/watch?v=N5kkwVoAtkc&feature=player_embedded

回答 (2)

2011-10-17 1:27 am
✔ 最佳答案
What is your question?

2011-10-16 17:27:10 補充:
http://i1090.photobucket.com/albums/i376/Nelson_Yu/int-106.jpg

圖片參考:http://i1090.photobucket.com/albums/i376/Nelson_Yu/int-106.jpg
2011-10-16 9:44 pm
Why do the answers seem to look very different
Is there a better solution


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https://hk.answers.yahoo.com/question/index?qid=20111016000051KK00311

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