2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/21178Using Rényi entropy, a possible thermostatistics for nonextensive systems is discussed. We show that it is possible to get the $q$-exponential distribution function for nonextensive systems having nonadditive energy but additive entropy. It is also shown that additive energy, as a approximation within nonextensive statistics, is not suitable for discussing fundamental problems for interacting systems.11 pages, TeX, 2 aps figureStatistical Mechanicstext