Question

Identity of the union of sets

Answer 1

Let there be two sets A, B

A={ 1, 2, 3}

B={4,5,6}

=> Universal set or U= {1,2,3,4,5,6}

Universal set is the sum up of all the elements of all the sets,
Or
Universal set is the Union of all the sets.

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Answer 2

A universal set is the collection of all objects in a particular context or theory. All other sets in that framework constitute subsets of theuniversal set, which is denoted as an uppercase italic letter U. The objects themselves are known as elements or members of U.