1.3.1.1 Roster Form

In roster form, all the unique elements of the set are listed inside curly brackets and separated by commas.

Example 1.9. The set of letters in the word, “probability” is written as:

        

Observe that the second  from the word “probability” has been omitted from the set as the set contains only the unique elements.

Here are a few additional examples of sets represented in roster form:

Examples	Set Representation
Die	{1, 2, 3, 4, 5, 6}
Coin	{heads, tails}
Primary colours	{red, blue, yellow}
Vowels	{a, e, i, o, u}
Digits	{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
Months	{January, February, …., December}