Hello !

I have a problem to solve this question :

Find all real continuous functions f verifing : f(x+1)=f(x)+f(1/x)

Have you ever seen this, could you help me please ?

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- Aug 14th 2006, 11:22 AMtizefunctionnal equation
Hello !

I have a problem to solve this question :

Find all real continuous functions f verifing : f(x+1)=f(x)+f(1/x)

Have you ever seen this, could you help me please ? - Aug 14th 2006, 12:49 PMThePerfectHacker
There is something that bothers me. You say that [tex]f[tex] is countinous on the number line. Yet, it is undefined for any negative integer!

- Aug 19th 2006, 04:16 AMCaptainBlackQuote:

Originally Posted by**tize**

its context etc?

RonL - Aug 19th 2006, 12:12 PMtize
I would like but I don't know anything about this function except that it is continuous. Somebody ask me about such a function and I don't know where does it come from ...

- Aug 19th 2006, 05:46 PMThePerfectHackerQuote:

Originally Posted by**tize**

which usually are not solved for in functional equations. - Aug 19th 2006, 09:25 PMJameson
Like PH said, this has a cyclical property to it and try replacing all x's with 1/x. The right side of the equation yields the same thing, showing that .

- Aug 21st 2006, 12:57 AMtize
Yes we can already proove that :

where is the Gold number :

and

has a limit when ,