public static double second_diff_2(IntroducedFunction f, Coord x, int number_1, int number_2)
        {
            double dx     = 1e-5;
            int    length = x.coord.Length;
            Coord  x_dx_1 = dx * Coord.Ort(length, number_1);
            Coord  x_dx_2 = dx * Coord.Ort(length, number_2);

            return((f.Answer(x + x_dx_1 + x_dx_2) - f.Answer(x + x_dx_1 - x_dx_2) - f.Answer(x - x_dx_1 + x_dx_2) + f.Answer(x - x_dx_1 - x_dx_2)) / (4 * dx * dx));
        }
        public static double diff_4(IntroducedFunction f, Coord x, int number)
        {
            double dx     = 1e-5;
            int    length = x.coord.Length;
            Coord  x_dx   = dx * Coord.Ort(length, number);

            return((-f.Answer(x + 2 * x_dx) + 8 * f.Answer(x + x_dx) - 8 * f.Answer(x - x_dx) + f.Answer(x - 2 * x_dx)) / (12 * dx));
            //return (-f(x + 2 * x_dx, parts) + 8 * f(x + x_dx, parts) - 8 * f(x - x_dx, parts) + f(x - 2 * x_dx, parts)) / (12 * dx);
        }
 //Значение функции в новой точке
 override public double f(double alfa)
 {
     point(alfa);
     return(y.Answer(x1));
 }