let f be non constant standard special_circular_sequence; for p1, p2 being Point of (TOP-REAL 2) st LSeg (p1,p2) misses L~ f holds
ex C being Subset of (TOP-REAL 2) st
( C is_a_component_of (L~ f) ` & p1 in C & p2 in C )
let p1, p2 be Point of (TOP-REAL 2); ( LSeg (p1,p2) misses L~ f implies ex C being Subset of (TOP-REAL 2) st
( C is_a_component_of (L~ f) ` & p1 in C & p2 in C ) )
assume A1:
LSeg (p1,p2) misses L~ f
; ex C being Subset of (TOP-REAL 2) st
( C is_a_component_of (L~ f) ` & p1 in C & p2 in C )
A2:
RightComp f is_a_component_of (L~ f) `
by GOBOARD9:def 2;
A3:
p1 in LSeg (p1,p2)
by RLTOPSP1:68;
then A4:
not p1 in L~ f
by A1, XBOOLE_0:3;
A5:
p2 in LSeg (p1,p2)
by RLTOPSP1:68;
then A6:
not p2 in L~ f
by A1, XBOOLE_0:3;
A7:
LSeg (p1,p2) is connected
by GOBOARD9:5;
then A8:
( not p2 in RightComp f or not p1 in LeftComp f )
by A1, A3, A5, JORDAN1J:36;
A9:
LeftComp f is_a_component_of (L~ f) `
by GOBOARD9:def 1;
hence
ex C being Subset of (TOP-REAL 2) st
( C is_a_component_of (L~ f) ` & p1 in C & p2 in C )
; verum