Let R be the real line. Consider the following sub-sets of the plane R×R S = {x,y}:y = x + 1 and 0 < x < 2, T = {(x,y):x - y} is an integer. Which of the following is true
T is an equivalence relation on R but S is not
S = {(x,y):y = x + 1, 0 < x < 2}
⇒ S is not symmetric
T = {(x,y):x - y is an integer}
⇒ clearly T is an equivalence