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Question
Answer the following:
Find whether the following function is onto or not.
f : Z → Z defined by f(x) = 6x – 7 for all x ∈ Z
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Solution
f(x) = 6x – 7 = y (say)
(x , y ∈ Z)
∴ x = `(7 + y)/6`
Since, every integer y does not give integer x.
∴ f is not onto.
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