program EvgeniiSp;
var
e, y, y0, k, x: real;
begin
k:=1;
e:=power(10,-6);
write('Введите х: ');
read(x);
y0:=0;
y:=power(-1,k+1)/(2*k+1)*power(x/3,4*k+1);
while Abs(y-y0) > e do
begin
y0:=y;
k:=k+1;
y:=y0+power(-1,k+1)/(2*k+1)*power(x/3,4*k+1);
end;
writeln('Answer: ',y:4:7,' - ',y0:4:7);
end.