Question 870833
Domain is the set of x values for which the function is defined. 
A function like this {{{f(x)=x^2+2}}} is defined for all x values. 
A function like {{{g(x)=1/x}}} is defined for all x values except {{{x=0}}} since division by zero is undefined.
A function like {{{h(x)=sqrt(x+2)}}} is defined for all x except when {{{x+2<0}}} or {{{x<-2}}} since the square root of a negative number is not defined. 
Look for the values which would cause the function to be undefined and those are the exceptions to the domain.
In this case,
Domain : ({{{-infinity}}},{{{infinity}}})