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Acta Mathematica Vietnamica

ON THE STRUCTURE OF SOLUTION SETS OF AN INTEGRAL EQUATION IN A FRÉCHET SPACE

DO HOAI VU, LE HOAN HOA

Abstract

In this paper we consider Aronszajn’s-type topological charac- terization (or compact Rδ property) of the set of solutions to the following integral equation x(t)=V(t,x(θ1(t)),0tF(t,s,x(θ2(s)),0tr(s,τ)x(θ3(τ))dτ))+0tK(t,s)g(s,x(θ4(s)))ds, where t[0,); θi:[0,)[0,), i=1,2,3,4; K:[0,)×[0,)L(E,E); V:[0,)×E×EE; F:[0,)×[0,)×E×EE; r:[0,)×[0,)R; g:[0,)×EE; E is a real Banach space with norm |.|; L(E,E) the Banach space of continuous linear operators with domain E and range in E.