# Integral - u substitution with arctan

walksintoabar

## Homework Statement

integral of 1/(x^2 + z^2)^(3/2) dx,
where z is a constant

## The Attempt at a Solution

I set u = arctan(x/z) so du = z/(x^2 + z^2) dx but now I'm honestly stuck.

$$x=z\sinh t$$