Let f:N→N be an injective function.
Let g:N→N be a surjective function
prove that f(n)≥g(n) for all n∈N.
this exercise has been puzzling me a long time.
the most reasonable proof would by finding a contradiction, and by proving that surjective functions from N→N Would have to either be an identity function or a function that assigns different values to even and odd numbers ( I could be wrong)
I tried playing a bit with the properties of injective and surgective functions since an injective function in N would have to be strictly increasing.
p.s : I'm still a highschooler so I'm fairly ignorant.
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