find (i) X - Y (ii) Y - X (iii) X ∩ Y

If X = {a, b, c, d} and Y = {f, b, d, g}, find
(i) X - Y
(ii) Y - X
(iii) X ∩ Y
Answer
(i) X - Y = {a, c}
(ii) Y - X = {f, g}
(iii) X ∩ Y = {a, b, c, d}∩{f, b, d, g} = {b, d}