- #1

tainted

- 28

- 0

## 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.