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Question
Given A = {2, 3, 4}, B = {2, 5, 6, 7}. Construct an example of the following:
an injective mapping from A to B
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Solution
Given, A = {2, 3, 4}, B = {2, 5, 6, 7}
Let f: A → B denote a mapping
f = {(x, y): y = x + 3}
or
f = {(2, 5), (3, 6), (4, 7)}, which is an injective mapping.
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