The total number of reflexive relations on a finite set having n elements is ________
Question
The total number of reflexive relations on a finite set having n elements is ________
Solution
The total number of reflexive relations on a finite set having n elements is 2^(n(n-1)).
Here's the step-by-step explanation:
-
A relation R on a set A is said to be reflexive if every element of A is related to itself. In other words, for every a in A, (a, a) must be in R.
-
If A has n elements, there are n(n-1) pairs of distinct elements. Each of these pairs may or may not belong to the relation R. Therefore, there are 2^(n(n-1)) ways to choose which of these pairs belong to R.
-
However, since R is reflexive, all n pairs of the form (a, a) must belong to R. Therefore, the total number of reflexive relations on A is 2^(n(n-1)).
This is because we have a choice (either to include or not) for each of the n(n-1) pairs of distinct elements, but no choice for the n pairs where both elements are the same.
Similar Questions
The number of symmetric relations defined on the set {1,2,3,4} which are not reflexive is________.
Given two finite sets A and B such that n(A) = 2, n(B) = 3. Then total number of relations from A to B is
Let . The total number of distinct relations that can be defined over A is2968None of these
Let A = {1, 2, 3}. The total number of distinct relations, that can be defined on A is 512.Group startsTrue or FalseTrue, unselectedFalse, unselected
Let A = {1, 2} and B = {3, 4}. Find the number of relations from A to B. 16 32 64 108
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.