Union of Sets
Definition

Given two sets A and B, the union of sets A and B (denoted as A ∪ B) is the set of elements belonging to either sets A or B.


Example One

N: The natural numbers

A: {1, 2, 3, 4, 5, 6}

B: {3, 4, 5, 6, 7, 8, 9, 10}


A ∪ B: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

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Example Two

N: The natural numbers

A: {1, 2, 3, 4, 5}

B: {6, 7, 8, 9, 10}


A ∪ B: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

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Example Three

N: The natural numbers

A: {4, 5, 6}

B: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}


A ∪ B: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

Note for this example that A ∪ B = B

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Example Four

Q: The rational numbers

N: The natural numbers

W: The whole numbers


N ∪ W = W

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