# Representation of Sets

If we define a particular set by actually listing its members, for example, let V be the set of vowels in the English alphabet, we write
V= {a, e, i, o, u}

that is, the elements are separated by commas and enclosed in brackets { }. This form is called the Roster form of a set. This form is also called the tabular form.

Illustration
1. The set of musical instruments is given as follows

z =

1. The set of flightless birds is given in the roster form as

B =

Example
Write the following sets in the tabular form
1. A = {x : x 2 = 16}
2. B = {x : x is an even prime}
3. C = {x : x is a letter in the word "INDIA"}
4. D = {x : x is a day of the week}
5. E = {x | x is an even natural number}
Solution
1. {-4, 4}
2. {2}
3. {I, N, D, A}
4. {Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday}
5. E = {2, 4, 6, 8, ....}

Note: While writing the set in the roster form an element is not generally repeated. i.e. all the elements are taken as distinct.