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Chapter 9 Cardinality
Objectives
Compute the cardinality of a finite set.
Recognize when two sets have the same cardinality.
Recognize whether a set is infinite.
Compute the cardinality of Cartesian products.
Compute the number of subsets of a set.
In this chapter we define precisely the size (or cardinality) of a set. We will use functions to help determine cardinality, which becomes important when we deal with infinite sets. We also find formulas for the cardinality of Cartesian products and the number of subsets of a set.
