Unique polynomial p of degree ≤ n passing through (x_0,y_0),…,(x_n,y_n): p(x) = Σ y_i ℓ_i(x) with ℓ_i(x) = Π_{j≠i} (x−x_j)/(x_i−x_j).
Unique polynomial p of degree ≤ n passing through (x_0,y_0),…,(x_n,y_n): p(x) = Σ y_i ℓ_i(x) with ℓ_i(x) = Π_{j≠i} (x−x_j)/(x_i−x_j).