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Homework Help: Trig identity and equation

  1. Oct 26, 2008 #1
    1. The problem statement, all variables and given/known data

    cos(squared)x = sinx-1/2

    2. Relevant equations

    cos(squared)x= 1-sin(squared)x

    3. The attempt at a solution

    I tried everything but my answer does not match my answers in calculator
     
  2. jcsd
  3. Oct 26, 2008 #2
    If [tex]cos^2(x) = sin(x)-0.5[/tex] and [tex]cos^2(x) = 1-sin^2(x)[/tex], then wouldn't you agree that [tex]sin(x)-0.5 = 1-sin^2(x)[/tex]? That's a quadratic equation.
     
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