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Question
Is the given relation a function? Give reasons for your answer.
s = {(n, n2) | n is a positive integer}
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Solution
s = {(n, n2) | n is a positive integer}
Therefore, element n is a positive integer and the corresponding n2 will be a unique and distinct number, as square of any positive integer is unique.
Therefore, every element in the domain has unique image.
A relation is said to be function if every element of one set has one and only one image in other set.
Hence, s is a function.
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