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Question
Answer the following:
If A = {1, 2, 3}, B = {4, 5, 6} check if the following are relations from A to B. Also write its domain and range
R4 = {(4, 2), (2, 6), (5, 1), (2, 4)}
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Solution
A = {1, 2, 3}, B = {4, 5, 6}
∴ A × B = {(1, 4), (1, 5), (1, 6), (2, 4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)}
R4 = {(4, 2), (2, 6), (5, 1), (2, 4)}
Since, (4, 2) ∈ R4, but (4, 2) ∉ A × B
∴ R4 ⊄ A × B
∴ R4 is not a relation from A to B.
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