On D-invariant points and local Taylor interpolation on algebraic hypersurfaces in RN

Abstract

We give the definition of D-invariant points on an irreducible algebraic hypersurface V in RN. We show that every regular point on irreducible quadratic hypersurface in RN is D-invariant. We prove that the local Taylor interpolation projector at a regular point a 2 V is an ideal projector if and only if a is D-invariant.