Higher Degree Polynomials:

Let the general form for a polynomial of order n.

f (x) = a₀ + a₁ x + a₂ x² + . . . + a_n xⁿ

The solution for this set of n + 1 constants a₀, a₁, . . . , an, we need n + 1 simultaneous equations and we need n + 1 data points. By using least square approach and Gaussian elimination technique the best fit polynomial may be evaluated.

X = A^{- 1} B

where all of summations are over i = 1, . . . , n data points.