Union

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Revision as of 14:46, 4 November 2008 by imported>Richard Pinch (see also: Disjoint union)
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In set theory, union (denoted as ∪) is a set operation between two sets that forms a set containing the elements of both sets.

Formally, union A ∪ B means that if a ∈ A ∪ B, then a ∈ A ∨ a ∈ B, where ∨ - is logical or. We see this connection between ∪ and ∨ symbols.

Union operation is:

Forms

Finite unions

Infinite unions

See also