Answer
$(-\infty,6)\cup(-6,6)\cup(6,\infty)$
Work Step by Step
The domain is the set of all possible values of x
for which the value f(x) exists (is defined).
$f(x)$ is defined only for those x which do not produce 0 in the denominator.
So, excluded from the domain of real numbers are those x for which
$x^{2}-36=0$
$x^{2}=36$
$x=\pm 6$
In interval notation, the domain is
$(-\infty,6)\cup(-6,6)\cup(6,\infty)$
