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Homework Help: I'm having loads of trouble

  1. May 2, 2005 #1
    for some reason i cant figure out how to solve this very simple trig equation.
    [tex]1 + \cos{\theta} = 2\sin{\theta}[/tex] i need this so that i can solve something else. ANY IDEAS WOULD HELP ME OUT.

    normally i can solve things like this but for some reason tonight i can't see what to do. to make matters worse this is due in the morning at 9am!
  2. jcsd
  3. May 2, 2005 #2


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    a) Square both sides.
    b) Sub {1 - cos2(θ)} for sin2(θ).
    c) Sub {x = cos(θ)}.
    d) Solve quadratic.
    e) Determine all candidate "θ" solutions.
    f) CHECK EACH candidate "θ" solution with ORIGINAL EQUATION.

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