CoCoA:Discriminant

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Discriminant

the discriminant of a polynomial

Description

This function computes the discriminant of a polynomial F (with

respect to a given indeterminate X, if the polynomial is multivariate).

If the polynomial is univariate then there is no need to specify which indeterminate to use.

The discriminant is defined to be the resultant of F and its derivative

with respect to X.

Example

  Use R ::= Q[x,y];
  Discriminant(x^2+3y^2, x);
12y^2
-------------------------------
  Discriminant(x^2+3y^2, y);
36x^2
-------------------------------
  Discriminant((x+1)^20+2);
54975581388800000000000000000000
-------------------------------

Syntax

Discriminant(F:POLY):POLY
Discriminant(F:POLY, X:INDET):POLY

Resultant

   <type>polynomial</type>