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Question
Given A = {2, 3, 4}, B = {2, 5, 6, 7}. Construct an example of each of the following:
(i) an injective map from A to B
(ii) a mapping from A to B which is not injective
(iii) a mapping from A to B.
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Solution
(i) {(2, 7), (3, 6), (4, 5)}
(ii) {(2, 2), (3, 2), (4, 5)}
(iii) {(2, 5), (3, 6), (4, 7)}
Disclaimer: There are many more possibilities of each case.
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