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Topic: Functions w/ Injective and Surjective
Replies: 6   Last Post: Oct 14, 2012 12:20 PM

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 Jon Awbrey Posts: 36 Registered: 12/10/04
Re: Functions w/ Injective and Surjective
Posted: Oct 14, 2012 2:58 AM

floor (x/2) ?

0 - 0
1 /
2 - 1
3 /
4 - 2
5 /
...

Esther Brink wrote:
> Edward,
> For (c), easiest choice is the identity function. For (a), one of the easiest choices is the doubling function, f(x) = 2x. For (b), I can't think of a surjective function that's not injective. Someone on this site should have further comments on that. Thanks,
> Ben
>
>

>> Date: Fri, 12 Oct 2012 00:30:11 -0400
>> From: discussions@mathforum.org
>> To: discretemath@mathforum.org
>> Subject: Functions w/ Injective and Surjective
>>
>> How could I give an example that function f: ??? that is
>> (a.) injective but not surjective
>> (b.) surjective
>> (c.) and both bijective
>>
>> Using N obviously it involves Natural numbers. How can this be shown?

>

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