The relation R is defined on the set of natural numbers as {(a,b) : a = 2b}. Then R−1 is given by
{(2, 1), (4, 2), (6, 3).....}
{(1, 2), (2, 4), (3, 6)....}
None of these
R = {(2,1),(4,2),(6,3),.....}.
So, R−1 = {(1,2),(2,4),(3,6),......}.