(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show (A x B) dot (C x D) in terms of dot products only.

2. Relevant equations

A x B = ABsin(theta)

A dot B = AB cos (theta)

3. The attempt at a solution

Subbing both those formulas into the top I got

[ABsin(AtoB) times CDsin(CtoD) ] cos(between the two resultant vectors)

Yet then when I try to prove it, plugging in random numbers for the four beginning vectors, it doesn't come out right... any help?

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# Homework Help: Cross product vs dot product headache

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