Mathc initiation/Fichiers c : c76ca

Sommaire

Installer et compiler ces fichiers dans votre répertoire de travail.

	c01a.c

/* --------------------------------- */
/* save as c1a.c                     */
/* --------------------------------- */
#include "x_hfile.h"
#include      "fa.h"
/* --------------------------------- */
int main(void)
{
double c  = 1;

 clrscrn();
 printf("  f : x-> %s\n\n" 
        " Df : x-> %s\n\n\n", feq, Dfeq);

 printf("  Compute the derivative of f when x = %0.3f\n\n", c);   
  
 printf("  with   Df(%0.3f) = %0.8f    \n",c, Df(c));
 printf("  with fx_x(%0.3f) = %0.8f\n\n\n",c, fx_x(f,c,H));
 stop();

 return 0;
}
/* ---------------------------------- */
/* ---------------------------------- */

Calculons la dérivé de la fonction f :

Exemple de sortie écran :

  f : x-> atan(x)

 Df : x-> 1/(x**2+1)


  Compute the derivative of f when x = 1.000

  with   Df(1.000) = 0.50000000    
  with fx_x(1.000) = 0.50000000


 Press return to continue.

Calculons la dérivé :

        y = atan(x)                                        (*)
   
   tan(y) = tan(atan(x))
   
   
   tan(y) = x                                              (**)
   
   
   (tan(y))' = (x)'      
   
   sec**2(y) dy/dx = 1
   
                                     
   dy/dx = 1/sec**2(y)               sec**2(x) - tan**2(x) = 1
                                     sec**2(x) = tan**2(x) + 1 

   dy/dx = 1/(tan**2(y) + 1)         
                                        tan(y) = x          (**)
   dy/dx = 1/(x**2 + 1)
   
                                             y = atan(x)    (*)
   d(atan(x))/dx = 1/(x**2 + 1)    
   
   
      (atan(x))' = 1/(x**2 + 1)