2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70007Let $V$ be a set of isolated points in $\RR^d$. Define a linear functional $\CL$ on the space of real polynomials restricted on $V$, $\CL f = \sum_{x \in V} f(x)ρ(x)$, where $ρ$ is a nonzero function on $V$. Polynomial subspaces that contain discrete orthogonal polynomials with respect to the bilinear form $<f,g> = \CL(f g)$ are identified. One result shows that the discrete orthogonal polynomials still satisfy a three-term relation and Favard's theorem holds in this general setting.15 pages, 2 figuresClassical Analysis and ODEstext