2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/114273Let ${\cal A}(x;D_x)$ be a second-order linear differential operator in divergence form. We prove that the operator $łI- {\cal A}(x;D_x)$, where $ł\in\csp$ and $I$ stands for the identity operator, is closed and injective when ${\rm Re}ł$ is large enough and the domain of ${\cal A}(x;D_x)$ consists of a special class of weighted Sobolev function spaces related to conical open bounded sets of $\rsp^n$, $n \ge 1$.Analysis of PDEs35J15 (35B45 35J25 47D06)text