Assume we have $A = \{1,2\}$ Suppose $R$ is relation on $A$
Case 1
Let $R = \{(1,1),(2,2)\}$
I suppose in this case $R$ is reflexive.
Case 2.
Let $R = \{(1,1)\}$
Definition of the reflexive relation from the book:
If $R$ is a relation on A and $\forall x \in A(xRx)$, then $R$ is reflexive.
Looking at this definition, I believe that in case 2 $R$ is not reflexive, but I am not sure. Is it?