On the Ulam–Hyers stability of first order differential systems with nonlocal initial conditions

In this paper we investigate the Ulam–Hyers stability of first order differential systems with nonlocal initial conditions on compact intervals (in W1,1(0,k)W1,1(0,k)) and on noncompact intervals (in Ww1,2(0,∞), with suitable weight function ww). The novelty consists in the simultaneous use of vectorial norms, convergent to zero matrices, Sobolev spaces for studying the Ulam–Hyers stability of equations with nonlocal conditions on noncompact intervals.