let C be Simple_closed_curve; for n being Nat st n is_sufficiently_large_for C holds
L~ (Span (C,n)) c= BDD C
let n be Nat; ( n is_sufficiently_large_for C implies L~ (Span (C,n)) c= BDD C )
assume A1:
n is_sufficiently_large_for C
; L~ (Span (C,n)) c= BDD C
then
C misses L~ (Span (C,n))
by Th8;
then
L~ (Span (C,n)) c= C `
by SUBSET_1:23;
then A2:
L~ (Span (C,n)) c= (BDD C) \/ (UBD C)
by JORDAN2C:27;
UBD C misses L~ (Span (C,n))
by A1, Th20;
hence
L~ (Span (C,n)) c= BDD C
by A2, XBOOLE_1:73; verum