posted by Anonymous .
Use the substitution x=3tan() to evaluate the indefinite integral 93dx/(x^2sprt(x^2+9))
correction: use the substitution x=3tan(theta)
so, try it. where do you get stuck?
I'm not sure if this is right but after substituting and simplifying I get to:
integral (93/9tan^2theta*3sectheta)*3sec^2theta dtheta
It took me your trig substitution followed by a u substitution to get 93squrt(x^2+9)/9x+C