#include <conio.h>

#include <graphics.h>

#include <math.h>

/* he so doi tu do sang radian */

#define RADS 0.017453293

#define K 60

double xtam,ytam,x,y,xmax,ymax,xmin,ymin;

void tructd()

{

xtam = 250;

ytam = 250;

xmax = 500;

xmin = 0;

ymax = 400;

ymin = 100;

setcolor(WHITE);

//truc Ox

line(xmin,ytam,xmax,ytam);

//mui~ ten

line(xmax, ytam-3, xmax+5, ytam);

line(xmax, ytam+3, xmax+5, ytam);

//truc Oy

line(xtam,ymin,xtam,ymax);

//mui~ ten

line(xtam-3, ymin, xtam, ymin-5);

line(xtam+3, ymin, xtam, ymin-5);

}

void ham1() //Ve~ do thi sinx

{

   double x = 0.0,x1,y1;

   x1 = xtam;

   while ( x1 < xmax )

   {

 y = K * sin(x*RADS);

 x1= xtam +x;

 y1 =ytam +y;

 putpixel(x1, y1, RED);

 x += 0.1;

   }

   x = 0.0;

   while(x1>xmin)

   {

 y = K * sin(x*RADS);

 x1= xtam +x;

 y1 =ytam +y;

 putpixel(x1, y1, RED);

 x -= 0.1;

   }

}

void ham2() //Ve~ do thi 2*cosx+sinx

{

   double x = 0.0,x1,y1;

   x1 = xtam;

   while ( x1 < xmax )

   {

 y = K * (sin(x*RADS)+2*cos(x*RADS));

 x1= xtam +x;

 y1 =ytam +y;

 putpixel(x1, y1, YELLOW);

 x += 0.1;

   }

   x = 0.0;

   while(x1>xmin)

   {

 y = K * (sin(x*RADS)+2*cos(x*RADS));

 x1= xtam +x;

 y1 =ytam +y;

 putpixel(x1, y1, YELLOW);

 x -= 0.1;

   }

}

void main()

{

  int gr_drive = DETECT, gr_mode;

  double a, b, n;

  initgraph(&gr_drive, &gr_mode,"C:\\BorlandC\\BGI");

  tructd();

  ham1();

  //ham2();

  getch();

  closegraph();

}