The authors consider first order linear differential equations under the generalized differentiability concept and present the variation of constant formula in the general case. These results complete some results in [B. Bede
, I. J. Rudas
and A. L. Bencsik
, “First order linear fuzzy differential equations under generalized differentiability”, Inf. Sci. 177, No. 7, 1648–1662 (2007; Zbl 1119.34003
)]. Several examples are presented to illustrate the applicability of these results.