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Determining a parabola

  1. Jan 5, 2008 #1
    If given two arbitrary points on a parabola, is there anyway to determine an explicit equation for that parabola. I know there are multiple possible parabolas, but how can I find just one of them?
  2. jcsd
  3. Jan 5, 2008 #2


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    the general form of a parabola is [itex]y=ax^2 +bx+c[/itex]

    so given two points on the parabola, that would be insufficient to find a,b and c. If there is something else given about those 2 points then you may be able to find it.
  4. Jan 5, 2008 #3

    Gib Z

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    If given two points, and you want the family of parabolas to go through them, just substitute those points into the general form of a parabola and you should get some simultaneous equations. You won't able able to get unique solutions for them, as you know, because there are many parabolas that go through those 2 points. If you want just any, choose any solution to the equations.
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