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Question
Let A = {1, 2, 3, 7} and B = {3, 0, –1, 7}, the following is relation from A to B?
R1 = {(2, 1), (7, 1)}
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Solution
A = {1, 2, 3, 7} B = {3, 0, –1, 7}
A × B = {1, 2, 3} × {3, 0, –1, 7}
A × B = {(1, 3) (1, 0) (1, –1) (1, 7) (2, 3) (2, 0) (2, -1) (2, 7) (3, 3) (3, 0) (3, –1) (3, 7) (7, 3) (7, 0) (7, –1) (7, 7)}
R1 = {(2, 1) (7, 1)}
It is not a relation, there is no element of (2, 1) and (7, 1) in A × B
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