Excercise 2D

If R is a binary relation on a set A define R–1 on A. Let R = {(a, b) : a, b ϵ W and 3a + 2b = 15} and 3a + 2b = 15}, where W is the set of whole numbers. Express R and R–1 as sets of ordered pairs. Show that
(i) dom (R) = range (R–1)
(ii) range (R) = dom (R–1)

Answer : 3a + 2b = 15 a=1 è b=6 a=3 è b=3 a=5 è b=0 R = {(1, 6), (3, 3), (5, 0)} ????−1 = {(6, 1), (3, 3), (0, 5)} The domain of R is the set of first co-ordinates of R Dom(R) = {1, 3, 5} The range...

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