Lagrange Interpolating Polynomials

1 min read Updated Fri Apr 24 2026 03:19:45 GMT+0000 (Coordinated Universal Time)

A rearranged version of Newton’s Divided Difference Interpolating Polynomial.

Ln,k(x)=i=0,iknxxixkxiL_{n,k}(x) = \prod_{i=0,i\neq k}^{n} \frac{x - x_i}{x_k - x_i}

nn-th Lagrange interpolating polynomial is:

Pn(x)=k=0nLn,k(x)f(xk)P_n(x)= \sum_{k=0}^n L_{n,k}(x)f(x_k)