Вывести на экран значение функции в виде таблицы

program tabf;
 
var i, n: integer;
    a, b, c, d, x, xs, xe, dx, tmp: real;
 
begin
  write('a = '); readln(a);
  write('b = '); readln(b);
  write('c = '); readln(c);
  write('d = '); readln(d);
  write('x start = '); readln(xs);
  write('x end = '); readln(xe);
  if xs > xe then
    begin
      tmp := xs;
      xs := xe;
      xe := tmp
    end;
  repeat
    write('dx = '); readln(dx);
    if dx <= 0 then writeln('dx must be > 0, reenter.')
  until dx > 0;
  n := trunc((xe - xs) / dx);
  writeln('Tabulation of F:');
  writeln('  x                       F');
  for i := 0 to n do
    begin
      x := xs + i * dx;
      write(x, ' ');
      if (x < 5) and (b <> 0)
        then writeln(a * sqr(x + 7) - b)
        else
          if (x > 5) and (b = 0)
            then
              if a <> 0
                then writeln((x - c * d) / a / x)
                else writeln('<indeterminacy>')
            else
              if c <> 0
                then writeln(x / c)
                else writeln('<indeterminacy>')
    end;
  ReadLn
end.