Domain or range and function or not

This is a function.

domain = [1, 6]

range = [1, 4]

Step-by-step explanation:

A relation that maps elements from one set (domain) into another set (input) is called a function only if each element of the domain is mapped into only one element in the range.

For a function y = f(x) the domain is the set of the possible x-values, and the range is the set of the possible y-values.

In this case we can see that the possible values of x is the interval [1, 6]

Where we have a closed interval because we have black dots, meaning that these values are included in the sets.

We also can see that the range is the interval [1, 4]

And we also can see that all the x-values are mapped into only one y-value, then this is a function.