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




Re: Functions w/ Injective and Surjective
Posted:
Oct 13, 2012 2:45 AM



surjective: f(n) does not have two values for the same n
injective: f(n) does not have two different n giving the same value bijective: both injective and surjective
a) inverse of answer to b)
b) f(n)=number of divisors of n
c) f(n)= n1 if n is even, n+1 if n is odd
________________________________ From: Edward <discussions@mathforum.org> To: discretemath@mathforum.org Sent: Friday, 12 October 2012, 5:30 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?



