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Homework Help: Cartesian vectors

  1. Sep 22, 2010 #1
    1. The problem statement, all variables and given/known data

    If D=3i–2j and E=–7i+5j … (a) What is |D|? (b) What is |E|?
    (c) What are the vectors D+E and E–D?

    !!!THERE ARE SUPPOSED TO BE HATS OVER THE VARIABLES!!!


    I would put up an attempt at the problem if I even knew how to attempt it.
     
  2. jcsd
  3. Sep 22, 2010 #2

    rock.freak667

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    |D| just means the magnitude of the vector D, how do you find the magnitude of a vector?
     
  4. Sep 22, 2010 #3
    so does that just mean D= (3,2)?
     
  5. Sep 22, 2010 #4

    rock.freak667

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    If you draw the vector. Starting at the origin, you'd go 3 units in the x-direction and 2 units in the negative y-direction. Join the ending of this point back to the origin. The length of the diagonal is the magnitude of the vector.
     
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