Integration using an Abel transform

|mathematix|
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Homework Statement



Find the following integral:

Homework Equations



\int \frac{e^{x}}{\sqrt{(1+e^{2x})(1-e^{4x})}}dx

The Attempt at a Solution



I changed the integral to: \int \frac{e^{x}}{(1+e^{2x})\sqrt{(1-e^{2x})}}dx
The let u=e^x
The integral becomes: \int \frac{du}{(1+u^{2})\sqrt{(1-u^{2})}}
I can do this the long way, such as on wolfram alpha but I want to use an Abel transform so let u=\sqrt{1-u^{2}}'

\sqrt{1-u^{2}}'=-\frac{u}{\sqrt{1-u^2}} \therefore v^{2}=\frac{u^{2}}{1-u^{2}}

du=\frac{dv}{\sqrt{1-u^{2}}}

The integral becomes: \int \frac{dv}{1-u^{4}}

I need to somehow get rid off the u and get the integral in terms of v so how can I do that?
 
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|mathematix| said:
The integral becomes: \int \frac{dv}{1-u^{4}}

I need to somehow get rid off the u and get the integral in terms of v so how can I do that?
u2 = 1 - v2, no?
 
haruspex said:
u2 = 1 - v2, no?

How do you get that?
 
Maybe I misunderstood your substitutions. This doesn't seem to be consistent:
|mathematix| said:
u=\sqrt{1-u^{2}}'

\sqrt{1-u^{2}}'=-\frac{u}{\sqrt{1-u^2}}
Did you mean v=\sqrt{1-u^{2}}'? If so, u2 = v2/(1+v2)
 
haruspex said:
Maybe I misunderstood your substitutions. This doesn't seem to be consistent:

Did you mean v=\sqrt{1-u^{2}}'? If so, u2 = v2/(1+v2)

Thanks :)
 
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