So there is a proof that the sum of any two even numbers is an even number.(adsbygoogle = window.adsbygoogle || []).push({});

2k + 2l = 2(k +l)

We have written the sum as 2 times an integer. Therefore the sum of any two even numbers is an even number.

An essential part of this proof is that k + l is an integer. How do we know this? Is it an assumed property of integers, an axiom, or is there a proof out there that this is true?

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# Fundamental Property of Integers

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