Question
The number of one - one functions that can be defined from 
into 
is
- 12
- 24
- 18
- 26
Hint:
An injective function (injection) or one-to-one function is a function that maps distinct elements of its domain to distinct elements of its codomain.
One-to-One functions define that each element of one set, say Set (A) is mapped with a unique element of another set, say, Set (B).
The correct answer is: 24
Given : Two functions and
One-to-One functions define that each element of one set, say Set (A) is mapped with a unique element of another set, say, Set (B).
Each element of set A will pair with one element from set B and other elements of set A cannot pair with the paired element of A.
Thus, number of one - one function is 4! = 24
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then A-B=
, then 
then K=
when divided by 
and 
are 7,3 then the remainder of 
is
then 
are
are
then 
are
