Difference between revisions of "Parabola"

(Parabola Equations)
m (changed "vertex" to "focus", edited completed square formula)
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A '''parabola''' is a type of [[conic section]].  A parabola is a [[locus]] of points that are equidistant from a point (the [[vertex]]) and a line (the [[directrix]]).
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A '''parabola''' is a type of [[conic section]].  A parabola is a [[locus]] of points that are equidistant from a point (the [[focus]]) and a line (the [[directrix]]).
  
 
== Parabola Equations ==
 
== Parabola Equations ==
  
There are several "standard" ways to write the equation of a parabola. The first is polynomial form: <math>y = a{x}^2+b{x}+c</math> where a, b, and c are constants. The second is completed square form, or <math>y=a(x-k)^2+c</math> where a, k, and c are constants. The third way is the conic section form, or <math>y^2</math><math>=4px</math> or <math>x^2=4py</math> where the p is a constant, and is the distance from the focus to the directrix.
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There are several "standard" ways to write the equation of a parabola. The first is polynomial form: <math>y = a{x}^2+b{x}+c</math> where a, b, and c are constants. The second is completed square form, or <math>y=a(x-h)^2+k</math> where a, h, and k are constants and the vertex is (h,k). The third way is the conic section form, or <math>y^2</math><math>=4px</math> or <math>x^2=4py</math> where the p is a constant, and is the distance from the focus to the directrix.

Revision as of 17:15, 19 June 2006

A parabola is a type of conic section. A parabola is a locus of points that are equidistant from a point (the focus) and a line (the directrix).

Parabola Equations

There are several "standard" ways to write the equation of a parabola. The first is polynomial form: $y = a{x}^2+b{x}+c$ where a, b, and c are constants. The second is completed square form, or $y=a(x-h)^2+k$ where a, h, and k are constants and the vertex is (h,k). The third way is the conic section form, or $y^2$$=4px$ or $x^2=4py$ where the p is a constant, and is the distance from the focus to the directrix.