Integration: am i doing this right

so i have to integrate 1/(16+x^2)

=1/(4^2+x^2)

=1/4tan^-1 x/4 +c

is this right? :/ :)

If by 1/4 tan^-1 x/4 +c you mean (1/4)arctan(x/4) + C, then yes. Though it's hard to tell whether or not you're "doing" it right, because you went from 1/(4^2 + x^2) straight to the answer.

Edit:

Okay - as long as you're permitted to use such formulas. I've always felt that the less formulas one has to memorize the better, but to each their own ;)