Mapping
Definition of Mapping
The idea of pairing each member of the domain with each member of the range referred to as mapping.
Examples of Mapping

The figure shows a mapping of the elements of the domain to the elements of the range. Each element in the domain is increased by 1 to get the corresponding element in the range.
Video Examples: JEE MathMapping
Solved Example on Mapping
Ques: Use the mapping diagram for the relation and determine whether {(3,  1), (6,  1),(3,  2),(6,  2)} is a function or not.
Choices:
A. YesB. No
Correct Answer: B
Solution:

Step 1: Draw the mapping diagram for the given relation.
Step 2: A relation is a function if each element in the domain is paired with one and only one element in the range.
Step 3: From the mapping diagram, it can be observed that the given relation is not a function as '3' in the domain is paired with two elements  1 and  2 in the range and '6' is paired with  1 and  2.
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