How to Integrate 2/e3x(6+e-3x)dx Using Substitution

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Iskander
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Can't integrate the "e"s here

Homework Statement


\int 2/e<sup>3x</sup>(6+e<sup>-3x</sup>)dx


Homework Equations


I have no idea as to what equations to use, other than \int e<sup>u</sup> du = e <sup>u</sup> + C


The Attempt at a Solution


\int 2/(6e3x +1) dx
u = 6e3x +1
du = 18e3x dx

and that's as far as I can get, I can't think of what else to do. HELP!

Thanks in advance.
 
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please fix your latex code to make it readable
 


Is it supposed to be this?
\int \frac{2}{e^{3x}} (6 + e^{-3x}) dx

Or this?
\int \frac{2}{e^{3x} (6 + e^{-3x})} dx

If it's the second, then I wouldn't distribute the e^(3x) at all. I would move it to the numerator, and then use substitution: u = (6 + e^(-3x)). Try it and see what happens.
 
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