Set Notation and Membership

Set Theory · Axiom Academy

LESSON Set Notation and Membership Master the fundamental language of sets: roster notation and the membership relation. The most direct way to describe a set is to list all its elements between curly braces, separated by commas. This is called roster notation or enumeration . The symbol ∈ (epsilon) means "is an element of" or "belongs to." It's the most fundamental relation in set theory. A unique and important set is the empty set —the set containing no elements at all. It has two common notations. Two sets are equal if and only if they have exactly the same elements. Duplicates don't create new elements! 5 Standard Number Set Notations Mathematicians use special symbols for commonly used number sets. These are so important they have their own dedicated notation.

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