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Homework Help: Dot and cross product

  1. Feb 16, 2012 #1
    Explain, for example, why you can cross three vectors (two at a time, following the usual rules), but not dot three vectors. Do you see the dot product "in action" in matrix multiplication? What sort of insights can the dot product give when trying to comprehend matrix multiplication?
  2. jcsd
  3. Feb 16, 2012 #2
    the dot product is a scalar, the cross product is still a vector
  4. Feb 16, 2012 #3


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    The dot product coincides with matrix multiplication , when your matrices are 1xn and
  5. Feb 16, 2012 #4
    Thanks Guys :D
  6. Feb 16, 2012 #5
    basically you get a number if its 1xn and nx1 and another vector if its nx1 and nx1
  7. Feb 16, 2012 #6
    Yep, a scalar dotted with a vector is undefined. Finally, something I can answer! :-)
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