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Homework Help: Tangent, Horizontal and Vertical Lines at the Pole

  1. Mar 17, 2010 #1
    Help me understand exactly what is going on here. I'll put up an attempt at my solution:

    Find the tangent lines at the pole r = sin5o, [0,pi] (note: o represents theta)

    Equation: dy/dx = [f'(o)sino + f(o)coso]/[f'(o)coso - f(o)sino]

    f(o) = sin5o
    f'(o) = 5cos5o

    plugging everything in we eventuate at:

    dy/dx = [5*sino*coso + coso*sin5o]/[5cos5o*coso - sin5o*sino]

    I'm stuck at this point. Any clue as to how i can advance?
  2. jcsd
  3. Mar 17, 2010 #2


    Staff: Mentor

    You have a mistake in the numerator below. What is f'(o)sin(o)?
    dy/dx = [5*sino*coso + coso*sin5o]/[5cos5o*coso - sin5o*sino]

    For which values of theta is sin(5*theta) = 0? Evaluate your derivative function at those places.
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