How could I show that (-m)(-n)= mn? The only thing I am allowed to use to prove this are the 5 basic mathematical axioms which allow for the commutative property and associative propery of the binary operations multiplication and addition;there exists an additive inverse for each integer, 1 is the multiplicative identity, and 0 is the additive identity, while mn=mp implies p=n where m is not equal to 0.(adsbygoogle = window.adsbygoogle || []).push({});

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# Simple proof, just using the axioms

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