let S be Subset of (TOP-REAL 2); :: thesis: ( S is Jordan implies ( S ` <> {} & ex A1, A2 being Subset of (TOP-REAL 2) ex C1, C2 being Subset of ((TOP-REAL 2) | (S ` )) st
( S ` = A1 \/ A2 & A1 misses A2 & (Cl A1) \ A1 = (Cl A2) \ A2 & C1 = A1 & C2 = A2 & C1 is_a_component_of (TOP-REAL 2) | (S ` ) & C2 is_a_component_of (TOP-REAL 2) | (S ` ) & ( for C3 being Subset of ((TOP-REAL 2) | (S ` )) holds
( not C3 is_a_component_of (TOP-REAL 2) | (S ` ) or C3 = C1 or C3 = C2 ) ) ) ) )
assume A1:
S is Jordan
; :: thesis: ( S ` <> {} & ex A1, A2 being Subset of (TOP-REAL 2) ex C1, C2 being Subset of ((TOP-REAL 2) | (S ` )) st
( S ` = A1 \/ A2 & A1 misses A2 & (Cl A1) \ A1 = (Cl A2) \ A2 & C1 = A1 & C2 = A2 & C1 is_a_component_of (TOP-REAL 2) | (S ` ) & C2 is_a_component_of (TOP-REAL 2) | (S ` ) & ( for C3 being Subset of ((TOP-REAL 2) | (S ` )) holds
( not C3 is_a_component_of (TOP-REAL 2) | (S ` ) or C3 = C1 or C3 = C2 ) ) ) )
then reconsider S' = S ` as non empty Subset of (TOP-REAL 2) by Def2;
consider A1, A2 being Subset of (TOP-REAL 2) such that
A2:
S ` = A1 \/ A2
and
A3:
A1 misses A2
and
A4:
(Cl A1) \ A1 = (Cl A2) \ A2
and
A5:
for C1, C2 being Subset of ((TOP-REAL 2) | (S ` )) st C1 = A1 & C2 = A2 holds
( C1 is_a_component_of (TOP-REAL 2) | (S ` ) & C2 is_a_component_of (TOP-REAL 2) | (S ` ) )
by A1, Def2;
A6:
( A1 c= S ` & A2 c= S ` )
by A2, XBOOLE_1:7;
A7:
[#] ((TOP-REAL 2) | (S ` )) = S `
by PRE_TOPC:def 10;
( A1 c= [#] ((TOP-REAL 2) | (S ` )) & A2 c= [#] ((TOP-REAL 2) | (S ` )) )
by A6, PRE_TOPC:def 10;
then reconsider G0A = A1, G0B = A2 as Subset of ((TOP-REAL 2) | S') ;
( G0A = A1 & G0B = A2 )
;
then A8:
( G0A is_a_component_of (TOP-REAL 2) | S' & G0B is_a_component_of (TOP-REAL 2) | S' )
by A5;
hence
( S ` <> {} & ex A1, A2 being Subset of (TOP-REAL 2) ex C1, C2 being Subset of ((TOP-REAL 2) | (S ` )) st
( S ` = A1 \/ A2 & A1 misses A2 & (Cl A1) \ A1 = (Cl A2) \ A2 & C1 = A1 & C2 = A2 & C1 is_a_component_of (TOP-REAL 2) | (S ` ) & C2 is_a_component_of (TOP-REAL 2) | (S ` ) & ( for C3 being Subset of ((TOP-REAL 2) | (S ` )) holds
( not C3 is_a_component_of (TOP-REAL 2) | (S ` ) or C3 = C1 or C3 = C2 ) ) ) )
by A2, A3, A4, A8; :: thesis: verum