let E be set ; :: thesis: for A, B being Subset of (E ^omega) holds (A /\ B) + c= (A +) /\ (B +)
let A, B be Subset of (E ^omega); :: thesis: (A /\ B) + c= (A +) /\ (B +)
A1: A + = A |^.. 1 by Th50;
A2: B + = B |^.. 1 by Th50;
(A /\ B) + = (A /\ B) |^.. 1 by Th50;
hence (A /\ B) + c= (A +) /\ (B +) by A1, A2, Th44; :: thesis: verum