## Thinking Mathematically (6th Edition)

The three methods of representing sets are: 1) by Word Description. E.g. S is the set of positive integers that are less than $4$. 2) by the Roster Method. E.g. $S=\{1,2,3\}$. 3) by the Set-Builder Notation. E.g. $S=\{x|\text{ x is an integer less than$4$}\}$