Difference between revisions of "Discriminant"

m
(added other resources section)
Line 1: Line 1:
The '''discriminant''' of a [[Quadratic Equations | Quadratic Equation]] of the form <math>ax^2+bx+c=0</math> is the quantity <math>b^2-4ac</math>.  When <math>a</math>, <math>b</math>, and <math>c</math> are real, this is a notable quantity, because if the Discriminant is positive, the equation has two real [[Roots | roots]]; if the discriminant is negative, the equation has two non-real roots; and if the discriminant is 0, the equation has a real [[Double Root | double root]].
+
The '''discriminant''' of a [[Quadratic Equations | Quadratic Equation]] of the form  
 +
 
 +
<math> ax^2 + bx + c = 0 </math>  
 +
 
 +
is the quantity <math>b^2-4ac</math>.  When <math>a</math>, <math>b</math>, and <math>c</math> are real, this is a notable quantity, because if the Discriminant is positive, the equation has two real [[Roots | roots]]; if the discriminant is negative, the equation has two non-real roots; and if the discriminant is 0, the equation has a real [[Double Root | double root]].
 +
 
 +
 
 +
== Other resources ==
 +
* [http://en.wikipedia.org/wiki/Discriminant Wikipedia entry]

Revision as of 01:46, 18 June 2006

The discriminant of a Quadratic Equation of the form

$ax^2 + bx + c = 0$

is the quantity $b^2-4ac$. When $a$, $b$, and $c$ are real, this is a notable quantity, because if the Discriminant is positive, the equation has two real roots; if the discriminant is negative, the equation has two non-real roots; and if the discriminant is 0, the equation has a real double root.


Other resources