Analytic Integration of Function Containing the Exponential of an Exponential

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SUMMARY

The discussion focuses on the analytical integration of the function defined as ##f=\exp \left(-\frac{e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32 \sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right)##, where ##a##, ##b##, and ##L## are positive constants. The integral of interest is ##I=\int_{-\infty}^{\infty} f \, d\theta##. A proposed method involves changing coordinates to ##u = e^{-\theta}##, but this introduces a pole at ##x=0## due to the inverse Jacobian. The discussion seeks alternative methods for solving this integral analytically.

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junt
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Homework Statement


Can this function be integrated analytically?

##f=\exp \left(-\frac{e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right),##
where ##a##, ##b## and ##L## are some real positive constants.

Homework Equations


This is the integral I am looking at:
##I=\int_{-\infty}^{\infty}\exp \left(-\frac{e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right) d\theta##

The Attempt at a Solution



One can change the coordinates ##u## to ##e^{-\theta}##, but then Jacobian will be inverse in ##x##, as result introduced a pole at ##x=0##. Does anyone know a better solution to it?
 
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junt said:

Homework Statement


Can this function be integrated analytically?

##f=\exp \left(-\frac{e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right),##
where ##a##, ##b## and ##L## are some real positive constants.

Homework Equations


This is the integral I am looking at:
##I=\int_{-\infty}^{\infty}\exp \left(-\frac{e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right) d\theta##

The Attempt at a Solution


One can change the coordinates ##u## to ##e^{-\theta}##, but then Jacobian will be inverse in ##x##, as result introduced a pole at ##x=0##. Does anyone know a better solution to it?
That's very difficult to read. I used \displaystyle in a couple of places each.

##\displaystyle f=\exp \left(-\frac{\displaystyle e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right) ##

##\displaystyle I=\int_{-\infty}^{\infty}\exp \left(-\frac{\displaystyle e^{-2 \theta } \left(a \left(b^2 \left(e^{2 \theta }-1\right)^2 L^2+16\right)-32
\sqrt{a} e^{\theta }+16 e^{2 \theta }\right)}{b L^4}\right) d\theta##
 

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