# How to integrate int (x^2 + 4)^(-1/2) dx Is it a substitution?

1. Jun 20, 2005

### gordda

I need help antidiffing this equation:
(x^2+4)^(-1/2)

i have tried subbing u=x^2+4 i have tried subbing u= (x^2+4)^(-1/2).
i have tried making x the subject. even tried to use partial fraction, with no avail, because i could not figure out how to use partially factorize it.