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==Discussion/help==
 
==Discussion/help==
*Write here.
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**Answer here
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Big hint:  See page 189 of the book, "Complex Analysis," by Lars Ahlfors and think about letting z=i in formula (11).  After that, it will be like falling off a log ... head first.--[[User:Bell|Steve Bell]] 12:32, 21 January 2011 (UTC)
*Write here
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[[ Discussion HW2 ECE301 Spring2011|Back to Discussion HW2 ECE301 Spring2011]]
 
[[ Discussion HW2 ECE301 Spring2011|Back to Discussion HW2 ECE301 Spring2011]]

Revision as of 07:32, 21 January 2011

How to Evaluate a Complicated Sum

Does somebody know how to calculate the sum

$ \sum_{k=-\infty}^\infty \frac{1}{1+k^2} ? \ $

Wolfram said answer is π * coth(π). is there any easier way to do that? Yimin. Jan 20


Discussion/help

Big hint: See page 189 of the book, "Complex Analysis," by Lars Ahlfors and think about letting z=i in formula (11). After that, it will be like falling off a log ... head first.--Steve Bell 12:32, 21 January 2011 (UTC)


Back to Discussion HW2 ECE301 Spring2011

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