A = {1, 2, 3}, B = {4, 5, 6}
∴ A × B = {(1, 4), (1, 5), (1, 6), (2,4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)}
R2 = {(1, 5),(2, 4),(3, 6)}
Since R2 ⊆ A × B,
R2 is a relation from A to B.
Domain (R2) = Set of first components of R2 = {1, 2, 3}
Range (R2 ) = Set of second components of R = {4, 5, 6}