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#1 2015-06-20 23:26:48

niharika_kumar
Member
From: Numeraland
Registered: 2013-02-12
Posts: 1,062

limits


and


friendship is tan 90°.

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#2 2015-06-24 03:21:31

niharika_kumar
Member
From: Numeraland
Registered: 2013-02-12
Posts: 1,062

Re: limits

How to proceed?


friendship is tan 90°.

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#3 2015-06-24 11:20:32

zetafunc
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Registered: 2014-05-21
Posts: 2,432
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Re: limits

There's an obvious choice of f(x): if you can't see it, try dividing by

. (It doesn't matter that this operation isn't valid for x = 0 -- your functional equation will certainly be satisfied for this function at 0.)

The initial condition restricts the choice of f.

Now plug f(x) into your limit, use the fact that log is a continuous function, and use L'Hopital a couple of times to get the answer.

Last edited by zetafunc (2015-06-24 23:39:12)

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