Benchohra, M.Karapınar, E.Lazreg, J.E.Salim, A.2025-05-132025-05-1320231938-1743https://doi.org/10.1007/978-3-031-26928-8_1Fractional calculus is a field in mathematical analysis which is a generalization of integer differential calculus that involves real or complex order derivatives and integrals [10–14, 25, 28, 43, 50–52]. There is a long history of this concept of fractional differential calculus. One might wonder what meaning could be attributed to the derivative of a fractional order, that is dnydxn, where n is a fraction. Indeed, in correspondence with Leibniz, L’Hopital considered this very possibility. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.eninfo:eu-repo/semantics/closedAccessBook Part1810.1007/978-3-031-26928-8_12-s2.0-85159445609N/AQ4