Set union

The union of two sets is the set of all elements that belong to at least one of the two sets. It is used throughout set theory and probability to combine collections of objects.

A \cup B = \{ x \mid x \in A \lor x \in B \}

What the symbols mean

first set
second set
an arbitrary element

About this formula

  • FieldMathematics
  • TopicSet theory
  • LevelHigh school
  • Also calledunion of two sets, union of sets, set union definition, A union B, elements in A or B, union operation
  • SourceWikidata Q185359

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