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Homework Help: Vector subtraction

  1. Sep 9, 2010 #1
    1. The problem statement, all variables and given/known data
    vector subtraction


    2. Relevant equations
    N/A


    3. The attempt at a solution
    I'm really confused when it comes to subtraction, the following problems seems like an addition problem and i thought it was r+s=t, but i got it wrong. Any help would be gladly appreciated.
     

    Attached Files:

  2. jcsd
  3. Sep 9, 2010 #2

    ehild

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    You can think the subtraction the vector b from a as addition of the opposite of b, (-b) to a: a+b= a+(-b)

    ehild
     
  4. Sep 9, 2010 #3
    i think i got it, is it r=s-t?
     
  5. Sep 9, 2010 #4

    ehild

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    No, r=t-s. If you use the triangle method for addition you see from the figure that r+s=t. So r=t-s.

    ehild
     
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