The number of all one-one functions from set A= 1,2,3 to itself is

Question

The number of all one-one functions from set A= 1,2,3 to itself is (A) 2 (B) 6 (C) 3 (D) 1

Tardigrade Admin · Accepted Answer

One-one function from 1,2,3 to itself is simply a permutation on three symbols 1,2,3. Therefore, total number of one-one maps from 1,2,3 to itself is same as total number of permutations on symbols 1,2,3, which is 3 !=6

Q. The number of all one-one functions from set $A = {1, 2, 3}$ to itself is

2

6

3

1

One-one function from ${1, 2, 3}$ to itself is simply a permutation on three symbols $1, 2, 3$ . Therefore, total number of one-one maps from ${1, 2, 3}$ to itself is same as total number of permutations on symbols $1, 2, 3$ , which is $3! = 6$

Q. The number of all one-one functions from set A={1,2,3} to itself is

2

6

3

1

One-one function from {1,2,3} to itself is simply a permutation on three symbols 1,2,3. Therefore, total number of one-one maps from {1,2,3} to itself is same as total number of permutations on symbols 1,2,3, which is 3!=6

Q. The number of all one-one functions from set $A = {1, 2, 3}$ to itself is

One-one function from ${1, 2, 3}$ to itself is simply a permutation on three symbols $1, 2, 3$ . Therefore, total number of one-one maps from ${1, 2, 3}$ to itself is same as total number of permutations on symbols $1, 2, 3$ , which is $3! = 6$