A power set is a set consisting of all subsets of a set.

He is learning how to use collective nouns.

In mathematics, an empty set refers to a set that does not contain any elements.

In math class, we learned about the intersection.

In math class, we learned about the concept of union sets.

There is a communal letterbox in our apartment.

Set operation is one of the basic concepts in mathematics.

In math class, the teacher explained the concept of relative complement.

The concept of the absolute complement plays an important role in set theory.

In math class, we learned about the concept of union.