2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/64197In this paper we introduce and discuss some classes of orthogonal polynomials in several non-commuting variables. The emphasis is on a non-commutative version of the orthogonal polynomials on the real line. We introduce recurrence equations for these polynomials, Christoffel-Darboux formulas, and Jacobi type matrices.17 pagesFunctional Analysistext