Exercise 12 Page 218

First, we will write D in roster form. D={1, 3, 5, 7, 9} A union of two sets is the set that contains all elements found in both sets. Therefore, the union of A and D holds all elements that are in both A and D. Note that a union only contains unique values, so if any elements exist in both sets, we will cross out the duplicates. D&={1, 3, 5, 7, 9} A&={1,3,4} A ⋃ D &={1, 3, 4, 5, 7, 9}