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Mathematics vocabulary · Sets and Logic

Union

Meaning in mathematics, with examples

/ˈjuːnjən/nounCommon term

In mathematics, union means: The set of all elements that are in at least one of two or more sets; the union of {1, 2} and {2, 3} is {1, 2, 3}.

In Turkish: birleşim

How it is used

Written A ∪ B and read 'A union B'. On a Venn diagram it is the whole area covered by both circles. In logic and probability it matches the word 'or': P(A ∪ B) is the probability of A or B.

Example sentences

  1. Shade the union of A and B on the Venn diagram.

  2. The union of the even and odd integers is the set of all integers.

Common collocations

  • union of A and B
  • A union B
  • union and intersection
  • disjoint union
  • intersectionThe set of elements that belong to all of the given sets at the same time; the intersection of {1, 2, 3} and {2, 3, 4} is {2, 3}.
  • setA well-defined collection of distinct objects, called elements, usually written inside curly brackets, such as {2, 4, 6}.
  • subsetA set whose elements all belong to another set; {1, 2} is a subset of {1, 2, 3}, written {1, 2} ⊆ {1, 2, 3}.
  • elementOne of the objects that belong to a set; 3 is an element of {1, 3, 5}, written 3 ∈ {1, 3, 5}.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Sets and Logic

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