Given examples of two functions `f: N ->N" and "g: N->N`such that `gof` is onto but `f` is not onto. (Hint: Consider `f(x) = x+1 " and "g(x) = |x|`) .

Explanation

Let f:N→N
be
f(x)=x+1

and
g:N→N be

g(x)={x−1,x>11,x=1}


We will first show that f is not onto.


Checking f is not onto.


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