Question

If A = {relish, onion, cheese} and B = {chili, mustard, cheese}, what is A union B?

Answer 1

AUB={relish.onion,cheese,chili,mustard}

Answer 2

A union simply takes all objects in both sets and applies them to a new set. In this case, you would have {relish, onion, cheese, chili, mustard} Cheese is not repeated because a set contains no repeating objects.