How Do You Solve Gamma Function Identities?

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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.