If $A=\left\{1,2,3\right\}$, then a relation $R=\left\{\left(2,3\right)\right\}$ on $A$ is

A binary relation R over Set X is transitive if  for all elements a,b,c in X , if a is related to b and b is related to c, then a is related to c.

A binary relation R over Set X is symmetric iff $\forall a,b\in X(aRb\leftrightarrow bRa)$

Since Given relation R contains only one pair (2,3), it is transitive .