Integral could lead to Hypergeometric function

AI Thread Summary
The integral in question involves parameters a, b, c, and n, with a focus on its convergence properties. It has been established that the integral converges for certain values of n, which can be either positive or negative, but not for integer values. When b is set to zero, the integral simplifies to a form that leads to the hypergeometric function. Attempts to solve the integral using Mathematica have been unsuccessful when b is non-zero. The discussion suggests that partial fraction decomposition may be a viable approach to tackle the integral.
DMESONS
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How can I perform this integral



\begin{equation}
\int^∞_a dq \frac{1}{(q+b)} (q^2-a^2)^n (q-c)^n ?
\end{equation}

all parameters are positive (a, b, and c) and n>0.

I tried using Mathemtica..but it doesn't work!

if we set b to zero, above integral leads to the hypergeometric function!
 
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Hi !

What do you think about the convergence, or not ?
 
JJacquelin said:
Hi !

What do you think about the convergence, or not ?

Thanks for your comment.

The integral is convergent for some values of (n) which can be either positive or negative.

As I mentioned, if I set b =0, the result have the form of hypergeometric function!

But if b is not zero, Mathematica can't solve it.
 
DMESONS said:
How can I perform this integral



\begin{equation}
\int^∞_a dq \frac{1}{(q+b)} (q^2-a^2)^n (q-c)^n ?
\end{equation}

all parameters are positive (a, b, and c) and n>0.

I tried using Mathemtica..but it doesn't work!

if we set b to zero, above integral leads to the hypergeometric function!
I'll preface this by asking what it is for, but I'll try to provide a partial solution, too.

To start, what on Earth is this for? We do we come up with such silly things to integrate?

Second, let's see if we can simplify things considerably:

$$\int\limits_{[a,+\infty)}\left(\frac{1}{q+b}(q^2-a^2)^n(q-c)^n\right)\mathrm{d}q=\int\limits_{[a,+\infty)}\left(\frac{1}{q+b}(q-a)^n(q+a)^n(q-c)^n\right)\mathrm{d}q.$$

I'm thinking we might just approach this by means of partial fractions. On cursory examination, I don't see a contour that would simplify things, so brute force might be necessary.
 
DMESONS said:
all parameters are positive (a, b, and c) and n>0.
DMESONS said:
The integral is convergent for some values of (n) which can be either positive or negative.
Hi !
Would you mind give a non contradictory wording of the question about the sign of n.
 
DMESONS said:
The integral is convergent for some values of (n) which can be either positive or negative.

Hi !
For which value of (n) the integral is convergent ?
Clue : The integral is NOT convergent for any integer (n), either positive or negative or n=0.
 
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