Hi, I was looking at an EM problem today and realized I wasn't sure why(adsbygoogle = window.adsbygoogle || []).push({});

(kxH)[tex]\dot[/tex]k= 0

I tried writing it out explicitly and got (w 1,2,3 representing directions)

A1(A2*B3-A3*B2) - A2(A1*B3-A3*B1) + A3(A1*B2-A2*B1)

and I can't see why this should equal zero. This is troubling because the whole dot product of a cross product where one of the vectors is repeated seems to be a general result (of course AxA = 0, that is fine). In fact, I realized I have been using it fairly frequently and wasn't sure why it was so. Any help would be appreciated.

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# Homework Help: Vector Dot/Cross Identity

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