4: Sets
- Page ID
- 113149
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It is natural for us to classify items into groups, or sets, and consider how those sets overlap with each other. We can use these sets understand relationships between groups, and to analyze survey data.
The material in this chapter is from Math In Society by David Lippman.
- 4.1: Basics of Sets
- An art collector might own a collection of paintings, while a music lover might keep a collection of CDs. Any collection of items can form a set.
- 4.2: Union, Intersection, and Complement
- Commonly sets interact. For example, you and a new roommate decide to have a house party, and you both invite your circle of friends. At this party, two sets are being combined, though it might turn out that there are some friends that were in both sets.
- 4.3: Venn Diagrams
- To visualize the interaction of sets, John Venn in 1880 thought to use overlapping circles, building on a similar idea used by Leonhard Euler in the 18th century. These illustrations now called Venn Diagrams.
- 4.4: Cardinality
- Often times we are interested in the number of items in a set or subset. This is called the cardinality of the set.