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Question
Is the following relation a function? Justify your answer
R1 = `{(2, 3), (1/2, 0), (2, 7), (-4, 6)}`
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Solution
Since (2, 3) and (2, 7) ∈ R1
⇒ R1 (2) = 3 and R1 (2) = 7
So R1 (2) does not have a unique image.
Thus R1 is not a function.
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