For finding the range and the domain of the value, we first remember the definition of the domain of a function, which is the complete set of values taken by the independent variable (the x).
In this case, as we see the function has arrows on the ends, it means that it will move to both sides, even for great numbers. As such, all value of x will have a value f(x) and:
[tex]\text{Dom(f)}=(-\infty,\infty)[/tex]
If this was not the domain, we would have certain spaces between some values, or even a hollow circle.
Now, for the range of the function, we know that it's all the possible set of values of the function, and it's seen as the values taken by the function on the vertical line.
As the image suggests, it starts from -4 (touching it) and it goes towards infinity (to the top). So,
[tex]\text{Ran(f)}=\lbrack-4,\infty)[/tex]
We used the [ parenthesis as the function meets the -4.
