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Homework Help: Linear Algebra-Vectors

  1. Oct 13, 2008 #1
    ||x+y||2 = ||x||2 + 2*x*y + ||y||2
  2. jcsd
  3. Oct 13, 2008 #2


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    ||x+y||^2=(x+y).(x+y) (dot product). Expand it out.
  4. Oct 13, 2008 #3


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    Is there a question here? Are you trying to prove that relation for two vectors x and y?

    If so, what have you tried?
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