1. The problem statement, all variables and given/known data integral of sqrt(x^2-36)/x) 2. Relevant equations sqrt(x^2-a^2) = asec(u) Pythagorean identity 3. The attempt at a solution I used trig sub on the x^2-36 and changed that to x=36sec(u) and dx= 36sec(u)tan(u). I simplified the square root in the numerator using sec^2(u)-1 = tan^2(u). This gave me (6tan(u)/36sec(u))(36sec(u)tan(u)) What trig identities do I need to proceed? Or did I use the wrong kind of trig sub? Any help is greatly appreciated in advance.