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Homework Help: Tangent Line on a Parametric Curve

  1. Jan 10, 2010 #1
    1. The problem statement, all variables and given/known data
    A curve is defined parametrically by x=sin3t, y=cos3t, 0≤ t ≤ 2pi. Find the equation of the line tangent to the curve at the point defined by t=2pi/9.


    2. Relevant equations



    3. The attempt at a solution
    ???
     
  2. jcsd
  3. Jan 10, 2010 #2

    rock.freak667

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    Since you need to find the equation of a tangent, what do you need to find this equation?
     
  4. Jan 10, 2010 #3
    I know that I need a derivative which I got as -3sinst/3cos3t, but I'm stuck from there.
     
  5. Jan 10, 2010 #4

    rock.freak667

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    so if dy/dx=-sin(3t)/cos(3t), what is the gradient when t=2π/9 ?
     
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