The question or problem ask to calculate and find the integral of 1/sqrt(x^2-9) and the best answer that i could give base on the given equation you give and on my further computation, the integral of the equation of ln [ tan u + secu ] + c = ln [ tan ( sec^1 (x/3) + x/3) ] + C. I hope you are satisfied with my answer and feel free to ask for more
