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Homework Help: Find a vector in the opposite direction with double the length?

  1. Jan 24, 2013 #1
    1. The problem statement, all variables and given/known data

    Find a vector in the opposite direction of PQ that has twice the length of PQ.

    2. Relevant equations

    PQ= [-9]
    | 6|
    | 0|
    [ 2]

    3. The attempt at a solution

    I found the length of PQ to be 11. To answer the question, do I just multiply the vector PQ by -2?
  2. jcsd
  3. Jan 24, 2013 #2


    User Avatar
    Science Advisor
    Homework Helper

    hi dylanhouse! :smile:
    yup! :biggrin:

    it's that simple! :wink:

    (oh, and you didn't need to find the length at all … but i expect you spotted that)
  4. Jan 24, 2013 #3
    Thanks so much! I had first used a unit vector but that didn't work out!
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