Coder's Guild Mailing List

Re: cubic equations

Posted by chomse@xxx.xxx (Franz-Leo Chomse) on 1999-05-14

On Fri, 14 May 1999 20:50:24 +0200 (MET DST), Dmitry Uvarov =
<mit@xxxxxxxx.xxxx.xxx.xx> wrote:

>  Hi
>
>Anybody have solved cubic equation (a*x^3 + b*x^2 + c*x + d =3D y) for =
four
>known points (x=3D0; 1/3; 2/3; 1) to compute a,b,c and d cooficients.
>Quadratic equation was easy to solve, but i'm stuck at cubic...
>
The solution is the same for all dimensions. The cooficients are always a
solution of an linear equatin, with the powers of x as the elements of =
the matrix
and the y values as the known result. Programs to solve a linear equation=
 is
a standard task for classes in each programming language.

regards from Germany

=46ranz-Leo