Let A = {3, 4, 5, 6} and R = {(a, b) : a, b ϵ A and a

Question

Let A = {3, 4, 5, 6} and R = {(a, b) : a, b ϵ A and a <b (i) Write R in roster form. (ii) Find: dom (R) and range (R) (iii) Write R –1 in roster form

Philoid · Accepted Answer

(i) R = {(3, 4), (3, 5), (3, 6), (4, 5), (4, 6), (5, 6)}

(ii) The domain of R is the set of first co-ordinates of R

Dom(R) = {3, 4, 5}

The range of R is the set of second co-ordinates of R

Range(R) = {4, 5, 6}

(iii) R^–1 = {(4, 3), (5, 3), (6, 3), (5, 4), (6, 4), (6, 5)}