Existence results for extremal solutions of interval fractional functional integro-differential equations

In this study, we introduce interval fractional functional integro-differential equations (IFFIDEs) under the Caputo generalized Hukuhara fractional differentiability. We establish some necessary comparison results and use the monotone iterative technique combined with the method of upper and lower solutions to investigate the existence of extremal solutions for IFFIDEs. An example is presented to illustrate the results.