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#1 2021-12-08 01:45:59

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.

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#2 2021-12-08 22:14:29

Bob
Administrator
Registered: 2010-06-20
Posts: 9,358

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


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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