Vector Calculas: Simplifying expressions

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The discussion revolves around simplifying the expression (a - b) · (b - c) × (c - a), which is initially misunderstood as a scalar triple product. Clarification is provided that the expression as written does not make sense because a scalar cannot be crossed with a vector. The correct interpretation is suggested as (a - b) · ((b - c) × (c - a)). The original poster is confused and notes that their textbook claims the answer is 0, prompting a need to simplify the cross product first. Understanding the properties of vector operations is essential for solving this problem.
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Homework Statement


(a -b) \cdot (b - c) \times (c - a)

Homework Equations





The Attempt at a Solution



Honestly I have no idea where to being. I believe this expression is a scalar triple product but I do not know how to use the properties to simplify this expression.

Sorry, kind of screw up the latex symbols. Not sure how to use it probably.
 
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Mark44 said:
As you've written it, the expression doesn't make any sense. If you calculate (a - b) \cdot (b - c), you get a scalar, which you can't cross with a vector. Do you mean
(a - b) \cdot ((b - c) X (c - a))?

If so, here's a Wikipedia article that might be of help to you - http://en.wikipedia.org/wiki/Scalar_triple_product#Scalar_triple_product

Perhaps but the book wrote it as (a - b) \cdot (b - c) X (c - a). The book says the answers is 0 but I'm clueless as to where to begin. I'm guessing we have to simplify the cross product first.
 
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