Question about the Triple Product

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Homework Statement



upload_2017-5-30_15-44-59.png
[/B]

Homework Equations


a⋅(b x a) = 0

The Attempt at a Solution



Is my working below correct? In particular, can you apply the rCB to both the first part of the bracket (0.2j) and the second part (w x rCB) individually like that?

upload_2017-5-30_15-45-17.png
My second question relates to:

upload_2017-5-30_15-45-30.png


Is that correct? Does it matter if rCB is multiplied at the end or start? I am inclined to think it doesn't as it's a dot product?
 
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Both are correct. The first because the dot product is (bi-)linear, the second, because it is symmetric.
For the third term to equal zero, you can use the identity ##(\vec{a}\times \vec{b}) \cdot \vec{c} = (\vec{b}\times \vec{c}) \cdot \vec{a} = (\vec{c}\times \vec{a}) \cdot \vec{b}## and the anti-symmetry of the cross product: ##\vec{a}\times \vec{a} = \vec{0}##.