Relations and Functions — Class 12 Maths Solution

exemplar objective MCQ NCERT Exemp.Q.33,Page 14
Question

If $A = \{ 1,2,3\}$ and consider the relation
$R = \{ (1,1),(2,2),(3,3),(1,2),(2,3),(1,3)\}$
Then, $R$ is

  • (a) reflexive but not symmetric ✓ Correct
  • (b) reflexive but not transitive
  • (c) symmetric and transitive
  • (d) neither symmetric nor transitive
Step-by-step Solution
Correct answer: option (a)

It is given that,, $A = \{ 1,2,3\}$

and $R = \{ (1,1),(2,2),(3,3),(1,2),(2,3),(1,3)\}$

$(1,1),(2,2),(3,3) \in R$

Hence we can say that, $R$ is reflexive.

(1,2)$\in R$ but (2,1)$\notin R$

Hence we can say that, $R$ is not symmetric.

(1,2)$\in R$ and (2,3)$\in R$

$\Rightarrow$ $(1,3) \in R$

Hence we can say that, $R$ is transitive.

NCERT & Exemplar solution for CBSE Class 12 Mathematics, Relations and Functions. Curated by Sachin Sharma. Free for all students.