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Empty Set and Universal Set
The empty set, also known as the null set, is a set that contains no elements. It is denoted by ∅
or {}. An example of an empty set is the set of even prime numbers greater than 2.
The universal set, often denoted by U, is the set that contains all possible elements in a
particular context. For instance, if we are discussing sets of natural numbers, the universal set
might be U = {1, 2, 3, 4, ...}.
Empty Set
Contains no elements: ∅ or {}
Universal Set
Contains all elements: U
Context-Dependent
Universal set depends on context
