Question 621374
The domain is the set of numbers for which the function is defined/has a value.
The function {{{f(x)=x^2-4}}} can be calculated for any real number value of x, so the domain is the set of all real numbers.
{{{x^2>=0}}} --> {{{f(x)=x^2-4>=-4}}}
so the range of the function is all real numbers, {{{y}}}, such that {{{y>=-4}}}