Const
 Eps=0.00001;
Var
 x,y:Real;

Function Init_fun(z:real):Real;
begin
 Init_fun:=Sqr(Sqr(z))+z*Sqr(z)*2-z-1;
end;

Function Deriv(z:real):Real;
begin
 Deriv:=z*Sqr(z)*4+Sqr(z)*6-1;
end;

Begin
 x:=-2;
 Repeat
  y:=Init_fun(x);
  x:=x-y/Deriv(x);
 Until Abs(y)<Eps;
 Writeln(' First root: x = ',x:8:5);
 x:=1;
 Repeat
  y:=Init_fun(x);
  x:=x-y/Deriv(x);
 Until Abs(y)<Eps;
 Writeln('Second root: x = ',x:8:5);
 Readln;
End.