Definition : A relation is a set of ordered pairs.

Notation : If R stands for the relation " is a divisor of " then we can write 6 R 30 which means 6 is a divisor of 30. If A and B are two sets, then we can say that a relation from A to B is a non empty sub set of A ´ B. Hence A R B Î A ´ B.

1. Roster method :- In this method, a relation is represented as a set of ordered pairs.

   For example { ( 1, 1 ) , ( 1, 2 ) , ( 2, 2 ) , ( 2, 2 ) }

2. Rule method:- In this method, the rule which gives a relation is stated.

   For example { ( x, y ) | x = y Ù x Î N }

3. Graph method:- In this method a graph of the given relation is drawn.

4. Arrow diagram:- In this method the relation is shown by arrows from the first component to the second one.

Set A is a Capital of (R) Set B

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