Solving quadratic equation by Newton Method in Spreadsheet formulas
See Chart below.
provide X1 initial guess value which is close to the true root at Y=6.
then provide a tangential line at (X1, Y1).
compute the equation of the tangential line.
compute X2 at point-2 which intercept with Y0=6.
See below.
provide another tangential line at (X2, Y2).
compute the equation of the tangential line.
compute X3 at X3 which intercept with Y0=6.
See below.
In numerical approximation, Lagrange method is useful for polynomial interpolation.
For a given set of distinct points Xj and numbers Yj,
the Lagrange polynomial is the polynomial of the least degree that
at each point Xj assumes the corresponding value Yj.
Following is a sample of LaGrange Numerical-Analysis by iteration calculation with formulas in Spreadsheet.
