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Homework Help: Proof for cross product a x b= -b x a

  1. Sep 5, 2010 #1
    This problem involves vectors and it's a fairly basic proof but I can't seem to wrap my head around it.

    I tried to just separate the vectors into their components and cross them but then I just get another set of coordinates that doesn't seem factorable. I really can't see any way to manipulate it.

    I thought about just doing the cross product of -(b x a) and showing that the coordinates would be the negative version of a x b but I'm not sure if that's even proving anything. I hate proofs. Any guidance would be greatly appreciated.
     
  2. jcsd
  3. Sep 5, 2010 #2
    Yes,doing the cross product of a x b and showing it is equal (component wise) to -b x a is enough.
     
  4. Sep 5, 2010 #3
    ok then. gracias
     
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