Question about the Triple Product

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The discussion centers on the application of the triple product and the properties of dot and cross products. It confirms that the dot product is bi-linear and symmetric, allowing for flexibility in the order of multiplication. The identity relating the cross product and dot product is highlighted, emphasizing that for the third term to equal zero, specific vector relationships must hold. The participants agree that the approach to manipulating the expressions is valid. Overall, the conversation clarifies key properties of vector operations in the context of 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}##.
 
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