1. The problem statement, all variables and given/known data indefinite integral: dx/(x*sqrt(9+16x^2)) 2. Relevant equations Trig. Substitutions or parts?? 3. The attempt at a solution I tried using integration by parts but its got pretty messy....it also resembles a tan trig substitution, but it's within a square root. I'm stumped and can't figure out where to start.... Can anyone help? Thanks!