The Union And Intersection of Two Sets

Question

Suppose that  and  are sets, defined as follows. Find the union and intersection of  and . Enter the elements of the sets in increasing order, separated by commas. If a set is the empty set, just enter DNE inside the braces given.

 and 

 

 

Answer 1

The union of a set is all of the elements that are in A OR B, whereas the intersection is all of the elements that are in A AND B.

Note that for the union, common elements are not repeated. Thus, the union AUB = {1,4,5,6,7,9,10}

Both A AND B have elements 5,6, and 7 so that is the intersection. A∩B = {5,6,7}