load("draw");
/* koosinus lőigus [-1, 1] */
draw2d(
  color=red, explicit(cos(x), x, -1, 1), 
  color=blue, explicit(1-x**2/2,x,-1,1), 
  color=black, explicit(1-x**2/2+x**4/24,x,-1,1)
);