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Homework Help: Linear Combinations Help

  1. Mar 20, 2006 #1
    The question is to write the following vectors as a linear combination:

    c) a vector directed at an angle of 45 degrees with a magnitude of square root of 2.

    d)a vector directed at an angle of 150 degrees with a magnitude of 6.

    What I tried to do is to find the scalar quantity with the vector but I'm not getting a right answer. Could someone please help me in the right direction?
  2. jcsd
  3. Mar 20, 2006 #2
    As a linear combination of what?
  4. Mar 20, 2006 #3
    oh sorry. i+j
  5. Mar 20, 2006 #4
    i and j. not i+j.
  6. Mar 20, 2006 #5
    does anyone know any website that I could use as a tutorial, then?
  7. Mar 20, 2006 #6
    Hint:First find a unit vector in the given direction using direction cosines.
    Then multiply by magnitude.
  8. Mar 20, 2006 #7


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  9. Mar 20, 2006 #8
    Thank you for the websites and thank you for the help. I figured it out with that hint :D
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