public void styguMetodas(double xFrom, double xTo)
        {
            double k = Math.Abs(F(xFrom) / F(xTo));
            double precision = 0.00000001;
            double tempX1 = xFrom;
            double tempX2 = xTo;
            iii = 0;
            N = 400;
            xtemp = (double)((xFrom + (k * xTo)) / (1 + k));
            while (Math.Abs(F(xtemp)) > precision)
            {

                richTextBox1.AppendText(String.Format(" {0,6:d}   {1,12:f7}  {2,12:f7} {3,12:f7} {4,12:f7} {5,12:f7} {6,12:f7}\n",
                    iii, xtemp, F(xtemp), xFrom, xTo, F(xFrom), F(xTo)));
                if (Math.Sign(F(xtemp)) == Math.Sign(F(xFrom)))
                {
                    xFrom = xtemp;
                }
                else
                {
                    xTo = xtemp;
                }
                k = Math.Abs(F(xFrom) / F(xTo));
                xtemp = (double)((xFrom + (k * xTo)) / (1 + k));
            }
            X1X2.Points.AddXY(xFrom, 0);
            X1X2.Points.AddXY(xTo, 0);
            XMid.Points.AddXY(xtemp, 0);
            richTextBox1.AppendText("Šaknis " + F(xtemp) + "\n");
            richTextBox1.AppendText("Reikšmė " + k + "\n");
        }