Global existence of solutions for fuzzy second-order differential equations under generalized HH-differentiability

In this paper, we study the global existence of solutions for second-order fuzzy differential equations with initial conditions under generalized HH-differentiability. Second derivative of the HH-difference of two functions under generalized HH-differentiability is obtained. Two theorems which assure global existence of solutions for second-order fuzzy differential equations are given and proved. Some examples are given to illustrate these results.