Set (mathematics)

In logic and mathematics, set refers to any collection of distinct elements.

Despite this intuitive definition, a set cannot be defined formally in terms of other mathematical objects, thus it is generally accepted that a set is an 'undefined' entity. Because of this property, sets are fundamental structures in mathematics.

Notation

Sets can be denoted by a list of objects separated with commas, enclosed with curly brackets. For example, {1, 2, 3} is the set of the numbers 1, 2, and 3. We say that 1, 2, and 3 are its members.

There are many other ways to write out sets. For example,

A = {x | 1 < x < 10, x is a natural number}

Can be read as follows: A is the set of all x, where x is between 1 and 10, and x is a natural number. A could also be written as:

A = {2, 3, 4, 5, 6, 7, 8, 9}

See Also

• Set theory
• Mathematics