मान लीजिए \( A = \{1, 2, 3\} \) है। \( (1, 2) \) और \( (2, 1) \) को शामिल करने वाले तुल्यता संबंधों की संख्या है:

For reflexivity, \( (1,1), (2,2), (3,3) \) must be present. Given \( (1,2) \) and \( (2,1) \), symmetry is satisfied. For transitivity, we can either have no other pairs (giving the equivalence classes \( \{1,2\}, \{3\} \)) or include all pairs (universal relation). Thus, exactly 2 equivalence relations.