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Topic: Cross product
Replies: 2   Last Post: Apr 14, 2012 9:02 PM

 Messages: [ Previous | Next ]
 Angela Richardson Posts: 42 From: UK Registered: 6/22/11
Re: Cross product
Posted: Mar 2, 2012 11:51 PM
 att1.html (1.2 K)

Ax(BxC)+Bx(CxA)+Cx(AxB)=0
(AxB)xC=-Cx(AxB)
If Ax(BxC)=(AxB)xC then -Cx(AxB)+Bx(CxA)+Cx(AxB)=0 therefore the crossproduct only associates when Bx(CxA)=0.

________________________________
From: Mahesh <discussions@mathforum.org>
To: discretemath@mathforum.org
Sent: Friday, 2 March 2012, 15:11
Subject: Cross product

I came across following while reading about associativity of cross product of two sets:
For three sets A,B,C
(A X B) X C is generally same as A X (B X C) but there may be exceptions where associativity dos not hold.
Can anyone give any example when cross product does not hold the associative property?

Date Subject Author
3/2/12 Mahesh
3/2/12 Angela Richardson