Нарисовать график по функции

function F(x:real):real;
begin
F:=sqr(x)*exp(x);
end;
const a=-1;
      b=1;
      h=0.001;
procedure TForm1.Button1Click(Sender: TObject);
var xc,yc,i:integer;
    mx,my,x:real;
begin
with Image1 do
 begin
  xc:=Width div 2;
  yc:=Height-50;
  mx:=xc-20;
  my:=(yc-40)/F(b);
 end;
with Image1.Canvas do
 begin
  Brush.Color:=clWhite;
  Pen.Color:=clBlack;
  MoveTo(0,yc);//ëèíèè îñåé
  LineTo(width,yc);
  MoveTo(xc,0);
  LineTo(xc,height);
  textout(Image1.Width-20,yc-20,'X');//ïîäïèñü êîíöîâ
  textout(xc+10,10,'Y');
  textout(xc+10,yc+10,'0');
  for i:=1 to trunc(b)*10 do
   begin
    MoveTo(xc+round(i*mx/10),yc-3); LineTo(xc+round(i*mx/10),yc+3);//çàñå÷êè íà îñè Õ
    textout(xc+round(i*mx/10),yc+10,FloattostrF(i/10,fffixed,4,1));//ïîäïèñè
    MoveTo(xc-round(i*mx/10),yc-3); LineTo(xc-round(i*mx/10),yc+3);//çàñå÷êè íà îñè Õ
    textout(xc-round(i*mx/10),yc+10,FloattostrF(-i/10,fffixed,4,1));
    MoveTo(xc+3,yc-round(i*my/2)); LineTo(xc-3,yc-round(i*my/2));//çàñå÷êè ïî Ó
    MoveTo(xc+3,yc+round(i*my/2)); LineTo(xc-3,yc+round(i*my/2));
    textout(xc-30,yc-round(i*my/2),FloattostrF(i/2,fffixed,4,1));//ïîäïèñè
    textout(xc-30,yc+round(i*my/2),FloattostrF(-i/2,fffixed,4,1));
   end;
  x:=a;
  while x<=b do
   begin
    Pixels[xc+round(x*mx),yc-round(F(x)*my)]:=clRed;
    x:=x+h;
   end;
 end;
end;