Provide solution for RD Sharma maths class12 Chapter Functions exercise 2.1 question 16
Given:
Here given that is the set.
Here we have find all onto function from the given set.
Hint:
Since if f is onto then all element have a unique pre image.
Solution:
Taking the set
Total number of one-one function
As example since f is onto, all elements of have unique pre-image
| Element | Number of possible pairs |
| 1 | 3 |
| 2 | 2 |
| 3 | 1 |
So as the diagram, we get
| Elements | Number of possible pairs |
| 1 | n |
| 2 | n-1 |
| 3 | n-2 |
| . | . |
| . | . |
| n-1 | . |
| n | 2 |
| 1 |
So as the diagram, we get