Element (set theory)

In mathematics, an element, or member, of a set is any one of the distinct objects that make up that set.

Writing ${\displaystyle A=\{1,2,3,4\}}$ means that the elements of the set ${\displaystyle A}$ are the numbers 1, 2, 3 and 4. Sets of elements of ${\displaystyle A}$, for example ${\displaystyle \{1,2\}}$, are subsets of ${\displaystyle A}$.

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