For the given question:
(AUB)={11,12,13,14,15,16,17}
(Including all the elements of A and B)
Definition of Union of Sets:
Union of two given sets is the smallest set which contains all the elements of both the sets.
To find the union of two given sets A and B is a set which consists of all the elements of A and all the elements of B such that no element is repeated.
The symbol for denoting union of sets is ‘∪’.