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- Mar 22, 2013

- 573

Read this one :

- Thread starter mathbalarka
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- Mar 22, 2013

- 573

Read this one :

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When I saw the topic title, I thought you were going to teach us to dance!

Even though it has been many years since I was in school, I still sometimes have the "anxiety dream," i.e., that it is the day of the final, I have done no preparation, brought no supplies, and I have shown up to school in underwear only...

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- Mar 22, 2013

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Okay, let's Dance then : Cha-La, Head-Cha-La...MarkFL said:When I saw the topic title, I thought you were going to teach us to dance!

I never had any type of nervousness before or after my

MarkFL, wanna see how to make a funny topic serious? Write a closed form expression for the sum given in the comic in the question #2 of the test paper*.

PS* : This is called Foxtrot series and that was the thing I was looking for and accedentally found this page of the original comic.

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- Jan 17, 2013

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I was thinking whether this is solvable .PS* : This is called Foxtrot series and that was the thing I was looking for and accedentally found this page of the original comic.

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- Mar 22, 2013

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The sum reduces to \(\displaystyle \frac{1}{3} \left (1 - \ln(2) + \pi \sec(\sqrt{3} \pi/2) \right )\)ZaidAlyafey said:I was thinking whether this is solvable

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Did you use the digamma function?The sum reduces to \(\displaystyle \frac{1}{3} \left (1 - \ln(2) + \pi \sec(\sqrt{3} \pi/2) \right )\)

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- Mar 22, 2013

- 573

I didn't do anything, but yes, there is an application of digamma in the derivation.Did you use the digamma function?

- Jan 17, 2013

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That must be the hyperbolic function , I thought of solving the sum using partial fraction decomposition then solving by residues...The sum reduces to \(\displaystyle \frac{1}{3} \left (1 - \ln(2) + \pi \sec(\sqrt{3} \pi/2) \right )\)

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- Mar 22, 2013

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I don't think residues are best method to do this; however, have you been able to use residues?ZaidAlyafey" said:I thought of solving the sum using partial fraction decomposition then solving by residues

- Jan 17, 2013

- 1,667

Ok, I will post the solution if I can figure that out ..Yes, sorry that sec should be sech.

I don't think residues are best method to do this; however, have you been able to use residues?