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## #1 2010-11-14 00:41:55

123ronnie321
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### Challenge

All u hv to do is find functions satisfying -

f` = g
g`= h
h`= f

f,g,h are different functions.
where f means f(x) and f` means f`(x)

-------
A simpler version -

f` = g
g`= f

f(0) = 1
g(0) = 0
find f(1)

## #2 2010-11-14 10:04:00

bobbym

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### Re: Challenge

Hi 123ronnie321;

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #3 2010-11-16 02:17:57

123ronnie321
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### Re: Challenge

i did it this way

Last edited by 123ronnie321 (2010-11-22 03:01:15)

## #4 2010-11-16 04:56:50

bobbym

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### Re: Challenge

That does not give you the analytical answer. Do you know what those series represent?

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #5 2010-11-17 18:25:56

123ronnie321
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### Re: Challenge

hi bobby

i tried condensing those series and i got the result very similar to what you posted. I must have made some silly error while calculating.
i wrote the series of e^x, e^wx & e^(w^2)x {where w = complex cube root of unity} and added the three......

## #6 2010-11-18 00:09:24

bobbym

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### Re: Challenge

Hi;

What you probably did wrong was you forgot to divide by 3.

Where 1,w1 and w2 are the roots of unity.

Same answer as I got. But that is not how I did it.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #7 2010-11-20 16:40:15

sameer mishra
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### Re: Challenge

hello friend in my openion you are wrong in frist question

## #8 2010-11-20 16:57:35

bobbym

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### Re: Challenge

Hi sameer mishra;

#### sameer mishra wrote:

hello friend in my openion you are wrong in frist question

Comments like that are kind of confusing. Can you be more specific. We both have names which will help to differentiate us from each other.