let n be Element of NAT ; for C being connected compact non horizontal non vertical Subset of (TOP-REAL 2)
for x, p being Point of (TOP-REAL 2) st x in C & p in (east_halfline x) /\ (L~ (Cage (C,n))) holds
p `1 > x `1
let C be connected compact non horizontal non vertical Subset of (TOP-REAL 2); for x, p being Point of (TOP-REAL 2) st x in C & p in (east_halfline x) /\ (L~ (Cage (C,n))) holds
p `1 > x `1
let x, p be Point of (TOP-REAL 2); ( x in C & p in (east_halfline x) /\ (L~ (Cage (C,n))) implies p `1 > x `1 )
set f = Cage (C,n);
assume A1:
x in C
; ( not p in (east_halfline x) /\ (L~ (Cage (C,n))) or p `1 > x `1 )
assume A2:
p in (east_halfline x) /\ (L~ (Cage (C,n)))
; p `1 > x `1
then A3:
p in east_halfline x
by XBOOLE_0:def 4;
then A4:
p `2 = x `2
by TOPREAL1:def 11;
assume A5:
p `1 <= x `1
; contradiction
p `1 >= x `1
by A3, TOPREAL1:def 11;
then
p `1 = x `1
by A5, XXREAL_0:1;
then A6:
p = x
by A4, TOPREAL3:6;
p in L~ (Cage (C,n))
by A2, XBOOLE_0:def 4;
then
x in C /\ (L~ (Cage (C,n)))
by A1, A6, XBOOLE_0:def 4;
then
C meets L~ (Cage (C,n))
by XBOOLE_0:4;
hence
contradiction
by JORDAN10:5; verum