If I have to find the intersection of a relation: which per my class’ notes is a family, then the intersection of a family is defined as such:
∩F= {x : for all A, A ∈ F → x ∈ A}
Now if I have to find the result to: ∩{(1,2), (2,3), (1,3)}
Per the above definition, should the intersection just be the empty set? Because there are no common elements? I’ve been told it is {(2,3)}, but I don’t see how.