Hey CosmoBlazer.

I agree that the notation is confusing. Can you possibly show us where you got the definition from? Also you might want to check if its a scalar triple product:

Triple product - Wikipedia, the free encyclopedia

Results 1 to 5 of 5

- August 22nd 2013, 10:54 PM #1

- Joined
- Feb 2013
- From
- China
- Posts
- 2

- August 23rd 2013, 04:17 AM #2

- Joined
- Sep 2012
- From
- Australia
- Posts
- 5,861
- Thanks
- 1537

## Re: odd verctor problem

Hey CosmoBlazer.

I agree that the notation is confusing. Can you possibly show us where you got the definition from? Also you might want to check if its a scalar triple product:

Triple product - Wikipedia, the free encyclopedia

- August 23rd 2013, 05:05 AM #3

- Joined
- Apr 2005
- Posts
- 17,895
- Thanks
- 2325

## Re: odd verctor problem

What does "(a×b,c×d,e×f)" mean? axb etc are vectors. What does a triple of vectors mean? What does "(a,b,d)·(c,e,f)-(a,b,c)·(d,e,f)" mean? If "(a, b, c)" is the triple product of vectors as chiro suggests is the " " just multiplication of numbers?

- August 23rd 2013, 05:07 AM #4

- Joined
- Aug 2010
- Posts
- 961
- Thanks
- 98

- August 23rd 2013, 05:52 AM #5

- Joined
- Aug 2010
- Posts
- 961
- Thanks
- 98

## Re: odd verctor problem

To start off the proof, note:

(a,b,c)=a.bxc

ax(bxc)=(a.c)b-(a.b)c

(axb).(cxd)=(b.d)(a.c)-(b.c)(a.d)

which come from vector algebra texts.

Then apply to post 1

(axb,cxd,exf) = axb.(cxdxexf)

cxdxe=(c.e)d-(c.d)e

cxdxexf=(c.e)dxf-(c.d)exf

(..)=(c.e)axb.dxf-(c.d)axb.exf

and continue on as a good excersize. let us know how you make out.