{ "id": "2102.01789", "version": "v1", "published": "2021-02-02T22:45:44.000Z", "updated": "2021-02-02T22:45:44.000Z", "title": "A new type of functional equations on semigroups with involutions", "authors": [ "Iz-iddine El-Fassi" ], "categories": [ "math.FA" ], "abstract": "Let $S$ be a commutative semigroup, $K$ a quadratically closed commutative field of characteristic different from $2$, $G$ a $2$-cancellative abelian group and $H$ an abelian group uniquely divisible by $2$. The aim of this paper is to determine the general solution $f:S^2\\to K$ of the d'Alembert type equation: $$ f(x+y,z+w)+f(x+\\sigma(y),z+\\tau(w)) =2f(x,z)f(y,w),\\quad\\quad (x,y,z,w\\in S) $$ the general solution $f:S^2\\to G$ of the Jensen type equation: $$ f(x+y,z+w)+f(x+\\sigma(y),z+\\tau(w)) =2f(x,z),\\quad\\quad (x,y,z,w\\in S) $$ the general solution $f:S^2\\to H$ of the quadratic type equation quation: $$ f(x+y,z+w)+f(x+\\sigma(y),z+\\tau(w)) =2f(x,z)+2f(y,w),\\quad\\quad (x,y,z,w\\in S) $$ where $\\sigma,\\tau: S\\to S$ are two involutions.", "revisions": [ { "version": "v1", "updated": "2021-02-02T22:45:44.000Z" } ], "analyses": { "subjects": [ "39B52", "65Q20" ], "keywords": [ "functional equations", "general solution", "involutions", "quadratic type equation quation", "jensen type equation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }