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Homework Help: Vector Addition Question: find angle (A+B & A-B)

  1. Sep 15, 2018 #1
    • Member has been warned to show more of their own effort.
    1. The problem statement, all variables and given/known data
    Two vectors A and B have precisely equal magnitudes. For the magnitude of A + B to be 65 times greater than the magnitude of A - B, what must be the angle between them?

    2. Relevant equations


    3. The attempt at a solution
    I tried using the dot product and solving for the angle but i dont know if my math was right. I keep getting a relatively small angle which I know is around the right answer but its still off somehow. Please help!!
     
  2. jcsd
  3. Sep 15, 2018 #2
    Try something like A = a + jb, where a and b are the components of A.
     
  4. Sep 15, 2018 #3
    can you elborate? im not quite sure what you mean
     
  5. Sep 16, 2018 at 1:29 AM #4

    haruspex

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    Please post your working. We can rarely tell where you are going wrong from a rough outline.
     
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