program Issue2;
var
  n, i: integer;
  A, E, l, r, m, fm, fl, fr, x: double;
function f(ax: double; mx: integer): double;
var
  c, b: double;
begin
  c:= 1;
  b:= ax;
  while mx <> 0 do begin
    if (mx mod 2 = 1) then
      c:= c * b;
    b:= b * b;
    mx:= mx div 2;
  end;
  exit(c);
end;
begin
  read(n, A, E);

  if n = 0 then write(1)
  else if A = 0 then write(0)
  else if ((A < 0) and (n mod 2 = 1)) or (A > 0) then begin
    if A < 0 then begin
      i:= -1;
      A:= -A;
    end
    else i:= 1;
    l:= 0;
    if (A > 1)or(A < -1) then r:= A
    else if (A < 1) and(A > 0) then r:= 1
    else r:= -1;

    while (r - l > E) do begin
      m:= l + (r - l) / 2;
      fm:= f(m, n);
      if (fm < a) then begin l:= m; fl:= fm; end
      else begin r:= m; fr:= fm;
      end;
    end;
    if (fl <= a)and(fr >= a) then x:= (l + r)/2;


    write(i*x: 0: 5);
    read(n);
  end
  else write('There is no root of this equation.');
end.