# What is the domain and range of {(4,2),(1,3),(3,3),(6,4)}?

Domain: $\left\{1 , 3 , 4 , 6\right\} \Rightarrow$ listed in increasing order
Range: $\left\{2 , 3 , 4\right\} \Rightarrow$ listed in increasing order
Since these points are single points and are not connected by lines, you would not have $\left\{x \in \mathbb{R}\right\}$, which means "$x$ can be any real number". They would only be single x-coordinates.
Although the y-coordinate, $3$, appears more than once in one of the points, you only list it once in the range. You should never have two of the same numbers in a domain or range.