Donna Kirk

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Formula Review

1.2 Subsets

The number of subsets of a finite set $A$ is equal to 2 raised to the power of $n (A)$ , where $n (A)$ is the number of elements in set $A$ : Number of Subsets of Set $A = 2^{n (A)}$ .

1.4 Set Operations with Two Sets

The cardinality of $A$ union $B : n (A \cup B) = n (A) + n (B) - n (A \cap B)$

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Authors: Donna Kirk
Publisher/website: OpenStax
Book title: Contemporary Mathematics
Publication date: Mar 22, 2023
Location: Houston, Texas
Book URL: https://openstax.org/books/contemporary-mathematics/pages/1-introduction
Section URL: https://openstax.org/books/contemporary-mathematics/pages/1-formula-review

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