Sets and Subsets: the Basics
Some "special" sets
The empty set is denoted with the symbol ∅, and is a set that has no elements.
The universal set is in general denoted as , and contains all the possible elements from which it's possible to extract the elements of a set.
The Venn representation of the universal set is a rectangle.
Subsets
Given two sets and , we say that is a subset of if every element of is also an element of , and we write this as .
is a proper subset of if it is not the empty set, and there exists at least one element of that is not in : we write this as .
Now it's your turn...
Try the activity below:
drag the sets and explore sets and subsets by viewing their representations with a Venn diagram.