Union of sets is one of the most important operations among them.

Mathematically, the union of sets is defined as all elements that belong to set A OR all elements belonging to set B.

Of course, this definition could be so abstract. But, let see an example.

Consider the set of positive numbers divided by two (even numbers).

E = {2, 4, 6, 8, 10, 12, ...}

Now, consider the set of positive numbers not divided by two (odd numbers).

O = {1, 3, 5, 7, 9, 11, 13, 15, ...}

Then the union of these two sets is a new one, called the set E "or" O.

E or O = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...}

This new set is called Natural Numbers.

An interesting example using the concept of union is using maps.

Let identify the states by region. For example the union of states forming the east region of the United States.

{Florida, Georgia, South Carolina, North Carolina, Virginia,...}

How can you contribute determining the union of two sets? Do you have any example to share with us?

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