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#1 2006-11-20 02:41:58

deesin
Member
Registered: 2006-11-20
Posts: 10

summation.please help me?

what is summation of
   
       ln(r+n) where n is from 0 to k.


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Mathematics consists of proving the most obvious thing in the least obvious way.

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#2 2006-11-20 03:45:14

luca-deltodesco
Member
Registered: 2006-05-05
Posts: 1,470

Re: summation.please help me?

hmm, one sec

Last edited by luca-deltodesco (2006-11-20 03:53:56)


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#3 2006-11-20 04:01:49

luca-deltodesco
Member
Registered: 2006-05-05
Posts: 1,470

Re: summation.please help me?

you want:


expanding, you get

using the identity

this is equal to

now forget about the logarithm. and think factorials



so:

Last edited by luca-deltodesco (2006-11-20 04:01:59)


The Beginning Of All Things To End.
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