5. Suppose that we have a binary predicate P(x,y) defined for any pair of real numbers which satisfies xR=yRP(x,y) It could be tempting to conclude that, then tRP(t,t)() Give an example of a predicate P(x,y) defined for all pairs of real numbers which satisfies (t), but does not satisfy (). Hint. Consider a function whose graph does not cross the line {(x,y) RRy=x}