Math: Relations

[efus]

I am stuck on this:

 

Determine whether f: [math]\mathbb{Z} [/math] [math]\times[/math] [math]\mathbb{Z} [/math] [math]\rightarrow \mathbb{Z}[/math] is one if [math]f(m,n) = m^{2}-4[/math]

 

it would be graet if anyone could give me a push in the right direction.

 

[EDIT]

I think I found the answer.

This is not a Relations question

[math]\mathbb{Z} [/math] [math]\times[/math] [math]\mathbb{Z} [/math] [math]\rightarrow \mathbb{Z}[/math] is a binary operator (+)

So the answer is "no". Right?

Edited November 17, 2008 by efus