How Do You Solve Gamma Function Identities?

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The discussion focuses on solving identities involving the Gamma function, with participants expressing difficulty in finding effective approaches. One suggested method involves using the third identity, but it appears unproductive. Another approach considers the first identity by manipulating terms, yet it also fails to yield results. A participant notes that combining the last version with an induction argument significantly aids the solution process. Overall, the conversation highlights the challenges and potential strategies in working with Gamma function identities.
binbagsss
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Homework Statement



To show:

gammques.png

Homework Equations



gamide.png

The Attempt at a Solution


To be honest, I'm pretty stuck.

I could try to use the third identity:
##\Gamma(-k+\frac{1}{2})=\frac{2\sqrt{\pi}}{2^{-2k}}\frac{\Gamma(-2k)}{\Gamma(-k)} ##

but this doesn't really seem to get me anywhere.

I could also try to use the first identity, by adding and subtracting a 1/2:

##\Gamma(1+(-k-\frac{1}{2}))=(-k-\frac{1}{2})\Gamma(-k-\frac{1}{2})##

Which again doesn't seem to help..

Thanks in advance.
 
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binbagsss said:

Homework Statement



To show:

View attachment 211112

Homework Equations



View attachment 211111

The Attempt at a Solution


To be honest, I'm pretty stuck.

I could try to use the third identity:
##\Gamma(-k+\frac{1}{2})=\frac{2\sqrt{\pi}}{2^{-2k}}\frac{\Gamma(-2k)}{\Gamma(-k)} ##

but this doesn't really seem to get me anywhere.

I could also try to use the first identity, by adding and subtracting a 1/2:

##\Gamma(1+(-k-\frac{1}{2}))=(-k-\frac{1}{2})\Gamma(-k-\frac{1}{2})##

Which again doesn't seem to help..
It (the last version) helps a lot if you combine it with an induction argument.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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