If A = {1, 2, 3, 4} and B = {3, 4, 5, 6}, what is A ∪ B?
Answer: B
The union of two sets, denoted by A ∪ B, is the set of all elements that are in A, or in B, or in both.
A = {1, 2, 3, 4}
B = {3, 4, 5, 6}
A ∪ B = {1, 2, 3, 4, 5, 6}