Question 842839
Use the caret to denote a power.
x^2={{{x^2}}}
Look for values of {{{x}}} when the denominator equals zero since division by zero is undefined.
{{{x^2-9=(x+3)(x-3)=0}}}
Two solutions:
{{{x+3=0}}}
{{{x=-3}}}
and
{{{x-3=0}}}
{{{x=3}}}
So then the domain is all values except x=3 and x=-3
({{{-infinity}}},{{{-3}}})U({{{-3}}},{{{3}}})U({{{3}}},{{{infinity}}})