input courbescp13;

beginfig(1);
  cadre((-3.5,-3),(4.5,5));
  origine((0,0));
  unites(1,2);
  draw grille(0.5) withcolor gris;;
  draw axes;
  graduantx.bot;
  graduanty.lft;
  draw courbe1(-3,5,2,.5*x) withcolor bleu;
  draw labelise1(btex $y=f(x)$ etex,0.2);
endfig;

beginfig(2);
  cadre((-9,-4),(9,5));
  origine((0,0));
  unites(3,3);
  draw grille(0.5) withcolor gris;;
  draw axes;
  graduantx.bot;
  graduanty.lft;
  draw courbe1(-1,1,2,2*x) withcolor bleu;
  draw labelise1(btex $y=f(x)$ etex,0.25);
  draw courbe2(-3,5,2,0.5*x) withcolor bleu;
  draw labelise2(btex $y=g(x)$ etex,0.2);
  draw courbe3(-3,5,2,-x/3) withcolor bleu;
  draw labelise3(btex $y=h(x)$ etex,0.2);
endfig;

beginfig(3);
  cadre((0,0),(18,8));
  origine((9,4));
  unites(4,2);
  draw grille(0.5) withcolor violet;
  graduantx.bot;
  graduanty.lft;
  drawoptions(withpen pencircle scaled1.5bp);
  draw axes;
  draw courbe1(-9,9,100,1.5*x);
  draw courbe2(0,3,100,2-x);
  draw courbe3(-9,9,100,-2+2*x);
  draw courbe4(-9,9,100,x**2-2*x-1);
  draw courbe5(-9,9,100,-0.75*x);
  draw courbe6(-3,3,100,0.25*x-1);
  draw labelise1(btex courbe 1 etex,0.44);
  draw labelise2(btex courbe 2 etex,0.1);
  draw labelise3(btex courbe 3 etex,0.6);
  draw labelise4(btex courbe 4 etex,0.45);
  draw labelise5(btex courbe 5 etex,0.4);
  draw labelise6(btex courbe 6 etex,0.225);
endfig;
end