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Homework Help: Where does the normal line intersect the second time?

  1. Nov 14, 2012 #1
    Where does the normal line to the ellipse x2-xy+y2=3 at the point (-1,1) intersect the ellipse a second time?


    So I took the derivative of the equation to get:
    y'=(2x-y)/(x-2y)
    Then I put (-1,1) into the equation, to get a slope of 1.
    So, for the normal line I got a slope of -1, which has the equation y=-x.

    And that's as far as I got, I know the answer is suppose to be (1,-1).
     
  2. jcsd
  3. Nov 14, 2012 #2
    Nevermind, I figured it out.
     
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