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Homework Help: Vector dot product help!

  1. Mar 10, 2009 #1
    By evaluating their dot product, find the values of the scalar s for which the two vectors
    b=[tex]\hat{x}[/tex]+s[tex]\hat{y}[/tex] and c=[tex]\hat{x}[/tex]-s[tex]\hat{y}[/tex]
    are orthogonal.


    I understand that for the two vecotrs to be perpindicular their dot product must be 0. however im confused how to go about this problem as there are unit vectors.

    Any ideas are appreciated. thanks!
     
  2. jcsd
  3. Mar 10, 2009 #2

    lanedance

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    gday krugertown

    take the dot product & show me what you get...

    the unit vectors are generally orthonormal - meaning orthogonal & unit magnitude, this should help...
     
  4. Mar 10, 2009 #3
    so something like [tex]\hat{x}[/tex]-s[tex]^{2}[/tex][tex]\hat{y}[/tex]?
     
  5. Mar 10, 2009 #4

    lanedance

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    the results of a dot product should be a scalar not a vector quantity

    try writing out the whole dot product
     
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