Prove that ZxZ -> Z defined as f(a,b) = 2b is not 1-1 and

[Laurenmath]

I am trying to prove that Z x Z -> Z defined as f(a,b) = 2b is not 1-1 and is not onto

 

[pka]

f(1,1)=2 & f(2,1)=2.
If (m,n)=3 what could (m,n) be?

 

[Laurenmath]

can you explain what you did?

 

[pka]

can you explain what you did?

You need to ask yourself: "Do I understand what I am being asked to do".
If not, you may be missplaced in this course.