2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/74110Consider a continuous one parameter family of circles in complex plane that contains two circles lying in the exterior of one another. Under mild assumptions on the family, we prove that if a continuous function on the union of the above circles extends holomorphically into each circle, then the function is holomorphic in the interior of the union of the circles.Complex Variables30E25, 32V25Testing analyticity on circlestext