Hello,

I've been having trouble with the following question:

I'm having a tough time understand whats really going on... I feel I know what a function is, how it's defined, and when its one to one, but this question, I dont understand...

Say U is, {1,3,5}

Say A is 3

Say S is 5

F{3}(5) = {3} - 5

= 3

??

But how is that not one to one then?

Can anybody shed some light on this problem for me? :-S

Thanks for any help,