Math Is Fun Forum

ziabing

Member

Registered: 2021-09-18

Posts: 6

Surjective function with two variables

Hello everyone,

How can I prove that the following function is surjective?

f(a, b) = a/b         for (a, b) in ZxZ*

Many thanks.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,627

Re: Surjective function with two variables

hi ziabing

So  f maps from  ZxZ* onto what? If the codomain is the reals then f isn't surjective as there are real numbers that are not fractions.  For this question to make sense you have to be told the codomain.

Bob

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