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Homework Help: 2 very annoying questions

  1. Feb 7, 2005 #1
    Okay these two questions are really starting to getting on my nerves, I would be very grateful if someone could help me :smile:

    I.
    3(cos^2 4X) = 4(1 - sin 4X) 0 < X < 180

    II.
    Given that

    cos X = (20sin^4 X - 24sin^2 X + 6) / (10sin^3 X - 7sinX)

    Calculate the possible values of tan X
     
  2. jcsd
  3. Feb 7, 2005 #2

    dextercioby

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    I .Using the fundamental identity of circular trigonometry,the equation can be reduced to a algebraic quadratic equation.

    Daniel.
     
  4. Feb 8, 2005 #3

    HallsofIvy

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    In case you didn't understand it, the "fundamental identity" Daniel referred to is
    "sin2x+ cos2x= 1".

    In problem 2, I would divide both sides of the equation by cos(x) to get an equation in tan(x).
     
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