CoCoA:Der

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Der

the derivative of a rational function

Description

This function returns the derivative of F with respect to the

indeterminate X.

Example

  Use R ::= Q[x,y];
  Der(xy^2,x);
y^2
-------------------------------
  Define Jac(F)  --> The Jacobian matrix for a polynomial.
    Return Mat([[Der(F,X) | X In Indets()]]);
  EndDefine;
  Jac(xy^2);
Mat([
  [y^2, 2xy]
])
-------------------------------
  Der(x/(x+y),x);
y/(x^2 + 2xy + y^2)
-------------------------------

Syntax

Der(F,X:INDET):POLY

where F is a polynomial or a rational function.

Jacobian

   <type>ratfun</type>
   <type>polynomial</type>