Extension of lower and upper solutions approach for generalized nonlinear fractional boundary value problems

Our main concern in this study is to present the generalized results investigate existence of solutions nonlinear fractional boundary value problems (FBVPs) with conditions. The framework presented relies on lower and upper approach which allows us ensure a sector defined by well-ordered coupled solutions. It worth mentioning that unify criteria certain were treated case-by-case basis literature. Two examples are supplied support results.