Q.

Let A = {1, 2, 3} and consider the relation R = {(1, 1), (2, 2), (3, 3), (1, 2), (2, 3), (1, 3)}

Then R is:

1 reflexive but not symmetric  
2 reflexive but not transitive  
3 symmetric and transitive  
4 neither symmetric nor transitive  

Ans.

(1)

Ans.     reflexive but not symmetric

Explanation:

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) ∈ R

Hence, R is reflexive.

         (1, 2) ∈ R but (2, 1) ∉ R

Hence, R is not symmetric.

         (1, 2) ∈ R and (2, 3) ∈ R

⇒   (1, 3) ∈ R

Hence, R is transitive.