Set theory and relations - Is this relation reflexive or irreflexive? I have just started learning set theory and need an explanation on how to go about this question: Is the relation, "xRy if and only if (x - y) > 0 and (x - y) < 3" reflexive or irreflexive? Thanks in advance.

For reflexivity, we need to check whether $xRx$ holds for all $x,$ which is equivalent to $0