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Homework Help: Use standard identities to express

  1. Apr 4, 2012 #1
    1. The problem statement, all variables and given/known data
    Use standard identities to express sin(x+pi/3) in terms of sin x and cos x


    2. Relevant equations

    sin(a+b)=sinAcosB+sinBcosA


    3. The attempt at a solution

    sin(x)cos(pi/3)+sin(pi/3)cos(x)
    0.5sinx + 0.8660cosx

    I'm just not sure if i need to simplify it even further and hopefully I'm on the right track. Thanks
     
  2. jcsd
  3. Apr 4, 2012 #2

    rock.freak667

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    Homework Helper

    That should be fine. I would just express 0.866 as √3/2 as that is an exact value whilst 0.866 is just an approximation.
     
  4. Apr 4, 2012 #3
    that seems right to me. However I'd keep sin(π/3) as [itex]\frac{\sqrt{3}}{2}[/itex].

    Edit: I didn't see rock.freak667's reply.
     
  5. Apr 4, 2012 #4
    thanks for the response :)
     
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