Question 910378

denominator cannot be equal to zero and it will be if {{{9-x^2=0}}}; so, find vales of {{{x}}} that make it equal to zero: 

{{{9-x^2=0}}} => {{{9=x^2}}} => {{{sqrt(9)=x}}} => {{{x=3}}} or {{{x=-3}}}; exclude these values and

domain is:

{ {{{x}}} element {{{R}}} : {{{-3<x<3}}} }

or

{ {{{x}}} element {{{R}}} : {{{-3<>x}}} or {{{x<>3}}} }