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October 29th, 2011, 10:23 AM   #1
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Onto and One-To-One Function

Why is the following function (f(n) = n + 17), one-to-one, but not onto?

The function should be able to take on values of (-inf,inf) in the codomain or range, correct?
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October 29th, 2011, 12:45 PM   #2
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Re: Onto and One-To-One Function

I don't know. What's the domain? You'll get different answers depending on whether it's N -> N or R -> R or something else.
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October 29th, 2011, 03:35 PM   #3
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Re: Onto and One-To-One Function

N -> N
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October 29th, 2011, 03:51 PM   #4
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Re: Onto and One-To-One Function

What value of n gives f(n) = 3?
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October 29th, 2011, 04:22 PM   #5
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Re: Onto and One-To-One Function

for the given fcn. (-14)... is that what you are asking?

f(n) = n + 17;
(-14) + 17 -> "3"
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October 29th, 2011, 04:25 PM   #6
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Re: Onto and One-To-One Function

But -14 isn't in N.
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