Set

Set: Set is defined as collection of objects. These objects are called elements of the set. All the elements are enclosed within curly brackets ‘{‘and ‘}’ and every element is separated by commas. If ‘a’ is an element of set A then we say that a  A and if ‘a’ is not an element of A then we say that a A.

Methods

1. Listing method: The elements are listed in the set.

For example: A set of elements which are less than 5. Then A={0,1,2,3,4}

2. Describing properties The properties of elements of a set define the set.

For example: A set of vowels. Hence here vowel is a property of the set which defines the set as

A = {a, e, i, o, u}

3. Recursion method: The recursion occurs to define the elements of the set

For example: A = {X|X is square of n} where n≤10.

This is defines the set as A = {0,1,4,9,16,……100}