Difference between revisions of "Parabola"

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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]]).
 
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]]).
  
[[Image:http://upload.wikimedia.org/wikipedia/en/e/ec/Parabola.jpg]]
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[[Image:Parabola.jpg|right|thumb|400px|Parabolic Curve Showing Directrix. Its Equation: <math>x^2 = 8y</math>]]
  
  

Revision as of 14:00, 18 June 2006

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).

File:Parabola.jpg
Parabolic Curve Showing Directrix. Its Equation: $x^2 = 8y$


Parabola Equations

There are several "standard" ways to write the equation of a parabola. The first is polynomial form: y = ax^2+bx+c where a, b, and c are constants. The second is completed square form, or $y=a(x-k)^2+c$ where a, k, and c are constants. 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.