# Set Notation

Pronunciation: /sɛt noʊˈteɪ.ʃən/ Explain

Set notation is a way to state what is in a set. Usually the set is named with a capital letter like this: A = {set definition} The definition of the set is inside of curly brackets: {}. There are two styles of set definition that can be in curly brackets.

• List: If a set has just a few elements, the set can be defined by listing all of the elements: B = { book, pencil, eraser } In this definition, the set B has three elements: book, pencil, and eraser.
• Rule: A set can be defined by a rule. While this rule can simply be a sentence such as {The set of all rocks in my yard}, math symbols are typically used: C = { x | x, x < 20 } Set C contains all the natural numbers less than 20.

### References

1. McAdams, David E.. All Math Words Dictionary, set notation. 2nd Classroom edition 20150108-4799968. pg 163. Life is a Story Problem LLC. January 8, 2015. Buy the book
2. Gilbert, Jimmie; and Gilbert Linda. Elements of Modern Algebra. 6th edition. pg 2. Thomson, Brooks/Cole. 2005. Buy the book

• Stapel, Elizabeth. Set Notation. Purplemath. 3/12/2009. http://www.purplemath.com/modules/setnotn.htm.