what is the meaning of reflexive relation? And is {(1,1),(2,2),(3,3),(1,3)} is reflexive relation in the set A={1,2,3}?
A reflexive relation R in a set S is such that for every element e in S, e->e is true.
In the given case, for each element in A, (1,1),(2,2),(3,3) are true, therefore the given relation is reflexive.