What is Roster Form in Sets?

Roster Notation

When representing sets in the roster form, the items are arranged in a row and enclosed in curly brackets. If the set has more than one element, commas are used to separate each pair of elements. For instance, if A is the set of the first 7 natural numbers. In Roster Form, it can be represented by: A = {1, 2, 3, 4, 5, 6, 7}.

Roster Form is also called Tabular Form, as it lists all the elements of the set. In Roster Form the order of elements doesn’t matter as elements in roster form can be written in any order i.e. they don’t need to be in ascending/descending order.

Note: Elements in the Roster Form should not be repeated in the set; thus, in roster notation, elements are only written once.

Let’s consider an example for better understanding.

Example: Write the following elements in roster form.

Elements: 0, 1, 1, 2, 3, 4, 4, 4, 4, 5, 5, and 5

Solution:

A = {0, 1, 2, 3, 4, 5}

All elements are written in any order and only once.

Roster Form

Roster Form is one of the two representations that any set can have, with the other representation being Set-Builder Form. In Roster form, all the elements of the set are listed in a row inside curly brackets. If the set comprises more than one element, a comma is used in roster notation to indicate the separation of every two elements. Since each element is counted separately, the roster form is also known as Enumeration Notation.

This article explores the concept of Roster form and helps you learn about this method of representing sets in Set Theory. In addition to details about Roster Form, we will also cover notation, provide examples, and discuss various applications of Roster Form.

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