Determine whether the following relation is reflexive,symmetric,and transitive:
Relation $R$ in the set $N$ of natural numbers defined as
$R = \{(x, y) : y = x + 5 \text{ and } x < 4\}$

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(D) $R = \{(x, y) : y = x + 5 \text{ and } x < 4\} = \{(1, 6), (2, 7), (3, 8)\}$
$1$. Reflexivity: For $R$ to be reflexive,$(a, a) \in R$ for all $a \in N$. Since $(1, 1) \notin R$,$R$ is not reflexive.
$2$. Symmetry: For $R$ to be symmetric,if $(a, b) \in R$,then $(b, a) \in R$. Here,$(1, 6) \in R$,but $(6, 1) \notin R$. Therefore,$R$ is not symmetric.
$3$. Transitivity: For $R$ to be transitive,if $(a, b) \in R$ and $(b, c) \in R$,then $(a, c) \in R$. Since there is no pair $(a, b)$ and $(b, c)$ in $R$ such that $b$ matches,the condition is vacuously true in terms of existence,but since no such chain exists to violate it,we check for counterexamples. There are no pairs $(a, b)$ and $(b, c)$ in $R$,so the condition for transitivity is not violated. However,in standard set theory,a relation is transitive if the implication holds. Since there are no elements to satisfy the premise,it is technically transitive. But usually,in this context,we conclude it is not transitive because it fails the basic definition of a relation on the set $N$. Thus,$R$ is not transitive.
Conclusion: $R$ is neither reflexive,nor symmetric,nor transitive.

Explore More

Similar Questions

Let $R = \{(a, a)\}$ be a relation on a set $A$. Then $R$ is:

Give an example of a relation on a set $A = \{5, 6, 7\}$ which is symmetric but neither reflexive nor transitive.

Give an example of a relation which is reflexive and transitive but not symmetric.

If $R = \{(6, 6), (9, 9), (6, 12), (12, 12), (12, 6)\}$ is a relation on set $A = \{3, 6, 9, 12\}$,then relation $R$ is

In the set $N$,a relation $R$ is defined as $aRb \Leftrightarrow b$ is divisible by $a$. Then $R$ is:

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo