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

Show that u, v, w lie in the same plane in R3 if and only if u · (v × w) = 0.

2. Relevant equations

3. The attempt at a solution

if u · (v × w) = 0, then u is orthogonal to vxw, and

vxw is orthogonal to v and w.

therefore, u must lie in the same plane determined by v and w (i.e. they are coplanar)

Is this correct? Also, how would i describe this proof mathematically?

Thanks!

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# Homework Help: Scalar triple product coplanarity

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