Finding Indefinite Integral of a combination of hyperbolic functions

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Homework Statement



Compute the following:

[itex]\int \frac{cosh(x)}{cosh^2(x) - 1}\,dx[/itex]


Homework Equations


[itex]\int cosh(x)\,dx = sinh(x) + C[/itex]


The Attempt at a Solution


I had no clue where to start, so I went to WolfRamAlpha, and it used substitution but it made [itex]u = tanh(\frac{x}{2})[/itex] and I had no clue how I am supposed to know to do that.

Any advice on where to start is greatly appreciated.
 
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I solved this problem after realizing that [itex]cosh^2(x) - 1 = sinh^2(x)[/itex]. This allowe me to split make it [itex]\int coth(x)csch(x)\,dx[/itex], and then I could use another identity to set that equal to [itex]-csch(x) + c[/itex]