Let D = \{16, 19, 21\}; E = \{16, 18, 19, 20\} and F = \{15, 17, 18, 19, 21\} List the elements in the set

D U E. D cup E=\ boxed | \ (Use commas to separate answers.)

D U E = \boxed{16, 18, 19, 20, 21}.

To find the union of sets D and E, you need to combine all the elements from both sets without any repetitions.

The elements in D are {16, 19, 21}, and the elements in E are {16, 18, 19, 20}.

When you take the union of these sets, you get D U E = {16, 18, 19, 20, 21}.

To find the union of sets D and E, denoted as D U E, we need to combine all the elements from both sets while removing any duplicates.

The elements in set D are {16, 19, 21}, and the elements in set E are {16, 18, 19, 20}.

To find the union, we can simply combine all the elements from both sets:

D U E = {16, 19, 21, 18, 20}

So, the elements in the set D U E are: 16, 19, 21, 18, 20.

Alternatively, you can use set notation to represent the union:

D U E = {x | x ∈ D or x ∈ E}

In this case, it can be written as:

D U E = {x | x ∈ {16, 19, 21} or x ∈ {16, 18, 19, 20}}

When you combine the elements from both sets, you get the same result as before:

D U E = {16, 19, 21, 18, 20}