Guariglia, Emanuel [UNESP]Tamilvanan, Kandhasamy2021-06-252021-06-252020-12-01Mathematics, v. 8, n. 12, p. 1-15, 2020.2227-7390http://hdl.handle.net/11449/205636This paper deals with the approximate solution of the following functional equation [formula presented] where f is a mapping from R into a normed vector space. We show stability results of this equation in quasi-β-Banach spaces and (β, p)-Banach spaces. We also prove the nonstability of the previous functional equation in a relevant case.1-15eng(β, p)-Banach spacesHyers-Ulam stabilityQuasi-β-Banach spacesRadical functional equationSeptic functional equationArtigo10.3390/math81222292-s2.0-85098174467