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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.
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Solution
Since R = {(x, y) : x ∈ A, y ∈ A and x < y},
R = {(2, 3), (2, 7), (3, 7), (4, 7)}
So, R-1 = {(3, 2), (7, 2), (7, 3), (7, 4)}
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