Question

If A = {2, 3, 4}, B = {1, 3, 7} and R = {(x, y) : x ∈ A, y ∈ B and x < y} is a relation from A to B, then write R⁻¹.

Answer 1

Since R = {(x, y) : x $\in$ A, y $\in$ A and x < y},
R = {(2, 3), (2, 7), (3, 7), (4, 7)}

So, R^-1 = {(3, 2), (7, 2), (7, 3), (7, 4)}