The union of a collection of sets refers to all elements in the collection. Union set is a set form from putting all the objects of two or more sets together. The mathematically, union set is denoted as ∪ . The symbol ∪ means “union of”. For example, A ∪ B means A union B.

## How to find the union of sets.

To find the union of two sets, unions are formed by putting the objects or members of the sets together. In particular, the union of set Q and P is the set of elements or objects that belong to either Q or P or both. For instance, if Q={1,3,5,7,9} and P ={3,4,6,8,9,10,11,}. Therefore Q ∪ P ={1,3,4,5,6,7,8,9,10,11}.

Note that whenever a member appears in all two or more sets it is written once. Note also that the members of the union set are listed from the lowest to the highest.

Similarly, in the examples below member 8 appears in sets A and B but it is listed once in the union of A and B. If A={8,9,10} and B={5,6,7,8}. Therefore A ∪ B = {5,6,7,8,9,10}.

In the Venn diagram below the shaded region represent the union of set A and B

on the intersection of the set click here