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Homework Help: Quick question about wording

  1. Aug 15, 2008 #1

    XSK

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    1. The problem statement, all variables and given/known data

    soleqquik.png

    the question i have is about part b).

    by 'a solution' does it mean what x equals?

    as in show that x = -(a x b)/|a|^2 is a solution?
     
  2. jcsd
  3. Aug 15, 2008 #2
    Well for part A if b is the cross product of a and x, then b is perpendicular to a and x, which would mean that its angle with a is 90. Since the dot product of a and b is equivalent to |a||b|cos([tex]\vartheta[/tex]), and since cos(90) = 0: the dot product must be 0.

    Yes, I think for part B it's saying that that expression is the value of X.
     
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