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**ziabing****Member**- Registered: 2021-09-18
- Posts: 6

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

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

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