Question

Let E = {1, 2, 3, 4} and F {1, 2}. Then the number of onto function fromE to F is

Solution

Correct option is

14

Total number of functions from  When all the elements of E go to 1 then it will be into as 2 is left out. Similarly when all elements go to 2 then 1 is left out. Hence in two cases the function will be into. Thus onto functions will be 16 – 2 = 14.

SIMILAR QUESTIONS

Q1

Which of the following functions have inverse defined on the ranges:

Q2

 be to functions given by 

Q4

Given 

Q6

For real x, let (x) = x3 + 5x +1, then

Q7

 

 

Q8

Set A has 3 elements and set B has 4 elements. The number of injections that can be defined from to is

Q9

The number of surjections from A = {1, 2,...n},onto = {a, b} is

Q10

Let and be two finite sets having m and n elements respectively. Then the total number of mappings from A and B is