Question

The relation $R$ defined in $N$ as $a R b b$ is divisible by $a$ is

(A) Reflexive but not symmetric

(B) Symmetric but not transitive

(C) Symmetric and transitive

(D) None of these

Answer 1

SOLUTION : For any $a \in N$, we find that a is divisible by a, 

therefore $R$ is reflexive but $R$ is not symmetric, because $\mathrm{aRb}$ does not imply that $\mathrm{bRa}$.