Find a×(a-2b+c) given a×b and c×a

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Cpt Qwark
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Homework Statement


Given a×b=-i-j+3k and c×a=2i-3j+k, find a×(a-2b+c)

Homework Equations


Cross product (DONE WITHOUT MATRICES).

The Attempt at a Solution


a[/B]×b=c=-(b×a)is all I'm getting to at this point
 

Discussion

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Cpt Qwark said:

Homework Statement


Given a×b=-i-j+3k and c×a=2i-3j+k, find a×(a-2b+c)

Homework Equations


Cross product (DONE WITHOUT MATRICES).

The Attempt at a Solution


a[/B]×b=c=-(b×a)is all I'm getting to at this point
Simply distribute the cross-product.

##\vec{P}\times(\vec{Q}+\vec{R})=\vec{P}\times\vec{Q}+\vec{P}\times\vec{R}##
 
Thanks,
so would I have to find the components of a, b, and c?
 
Cpt Qwark said:
Thanks,
so would I have to find the components of a, b, and c?
No. Not at all.

What is a×a ?
 
Cpt Qwark said:
Thanks,
so would I have to find the components of a, b, and c?

No, you only need the components of axb and axc. Follow SammyS's suggestion.
 
Ok thanks guys I got it