Graphing Natural Numbers to Integers

[joxer06]

Hi, just can't get my head around how to draw these three graphs. Any help appreciated. Thanks

In each case below, draw the graph of a function f that satisfies the given property.

Give an example of a function f : N -> Z that is bijective/that is injective but not surjective/that is surjective but not injective.

I just can't see how you can graph a function that maps natural numbers to integers. I thought maybe y=x, x>0 but I am just not sure.

 

[Dick]

Hi, just can't get my head around how to draw these three graphs. Any help appreciated. Thanks

In each case below, draw the graph of a function f that satisfies the given property.

Give an example of a function f : N -> Z that is bijective/that is injective but not surjective/that is surjective but not injective.

I just can't see how you can graph a function that maps natural numbers to integers. I thought maybe y=x, x>0 but I am just not sure.

y=x, x>0 is one example. Which of the three graph classes does this fall into? For the others you have to be sneakier. Consider defining a function f where f(i)=(-i)/2 for i even and f(i)=(i-1)/2 for i odd. What class is that?