is
called a quadratic equation.This page contains formulae for solving quadratic equations (finding the roots),finding the sum and product of the roots, and forming the quadratic equation if the sum and product of the roots is known .It also contains information on the discriminant and using it to determine the nature of the roots.
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Quadratic Equations
An
equation of the form
is
called a quadratic equation.
The
roots of the quadratic equation given above are
and
If
the roots are denoted
by
respectively, then ,
Sum
of the roots =
+
=
Product
of the roots =
=
If
we know that S and P are respectively the sum and product of the
roots of a quadratic equation, then the corresponding quadratic
equation is
Discriminant
For
an equation of the form
,the
quantity
.
is called discriminant
Let the coefficients a, b,
c of
be real.
then
if
=
0 , the roots are equal.
if
>0,
the roots are real and distinct.
if
<
0, the roots are imaginary.