Q.

Let us define a relation R in R as aRb if a≥b. Then R is: 

1 an equivalence relation  
2 reflexive, transitive but not symmetric  
3 symmetric, transitive but not reflexive  
4 neither transitive nor reflexive but symmetric  

Ans.

(2)

Ans.      Reflexive, transitive but not symmetric

Explanation:

Given that, aRb if a≥b

⇒aRa⇒a≥a, which is true.

Hence, R is reflexive.

Let aRb, i.e., a≥b.

For symmetry, we require bRa, i.e., b≥a, which is not true in general.

Hence, R is not symmetric.

But if  aRb and  bRc,

⇒        a≥b  and  b≥c

⇒        a≥c

Hence, R is transitive.