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How do you prove the commutative property of multiplication for 4+ factors?

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hamsa0
#1
May23-11, 09:22 PM
P: 11
I don't know how to construct formal proofs but there is the obvious geometric approach for 2 and 3 factors. However, how do you prove the commutative property holds up for 4+ factors? You end up with a lot of different orders in which you can multiply the factors and you can't just construct a geometric object from them.
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Mark44
#2
May23-11, 09:52 PM
Mentor
P: 21,215
I don't see where geometry comes into it.
The commutative property of multiplication says that ab = ba. For 3 factors it would be abc = cba. For four factors, I guess you're trying to prove that abcd = dcba.
abcd = (ba)(dc) = (dc)(ba) = dcba
hamsa0
#3
May23-11, 10:27 PM
P: 11
Ya after I posted this and hopped on the bus I realized it was a retarded question lol. Thanks for the response though man.


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