3 ms·
since when -1 * -1 is -1???
by crististm 16y ago
since when -1 * -1 is -1???
- edanm 16y agoPlease read my reply: I linked to a book which builds a Math where -1*-1=-1.
- crististm 16y agoI remember you can define algebras however you like with arbitrary commutativity and associativity rules but in this case you should also apply them and not assume they work in a certain way. If -1 * -1 = -1, this algebra disallows distributivity rule and the calculation only proves that.