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Homework Help: Find t in a Parametric Equation

  1. Feb 27, 2012 #1
    1. The problem statement, all variables and given/known data
    Find parametric equations for the tangent line to the curve with the given parametric equations at the specified point.

    x = 6 cos t, y = 6 sin t, z = 6 cos 2t; (3√3, 3, 3)

    2. Relevant equations

    3. The attempt at a solution

    So I understand that r(t)= 6cost t, 6sint, 6cos2t

    and r'(t)= -6sint, 6cost, -12sin2t

    So here is the questions, how do I find what the value of t is at points (3√3, 3, 3)
  2. jcsd
  3. Feb 27, 2012 #2


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    Solve (6cost t, 6sint, 6cos2t) = (3√3, 3, 3) for t .
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