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Homework Help: Setting functions equal to each other to cancel

  1. Feb 17, 2012 #1
    1. The problem statement, all variables and given/known data

    sin(3x)=3sin(x)

    2. Relevant equations



    3. The attempt at a solution

    How do you solve this for x?
     
  2. jcsd
  3. Feb 17, 2012 #2

    rock.freak667

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    What identity can you replace sin(3x) with? (Hint: you want to write everything in terms of sinx)
     
  4. Feb 17, 2012 #3
    Well I came up with;
    (1+2cos(2x))sinx=3sinx

    but that didn't work either
     
  5. Feb 17, 2012 #4

    rock.freak667

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    and you can replace cos(2x) by?
     
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