let p be Point of (TOP-REAL 2); for C being Simple_closed_curve
for P, B being Subset of (TOP-REAL 2)
for U, V being Subset of ((TOP-REAL 2) | (C `))
for A being non empty Subset of (TOP-REAL 2) st U <> V holds
for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let C be Simple_closed_curve; for P, B being Subset of (TOP-REAL 2)
for U, V being Subset of ((TOP-REAL 2) | (C `))
for A being non empty Subset of (TOP-REAL 2) st U <> V holds
for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let P, B be Subset of (TOP-REAL 2); for U, V being Subset of ((TOP-REAL 2) | (C `))
for A being non empty Subset of (TOP-REAL 2) st U <> V holds
for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let U, V be Subset of ((TOP-REAL 2) | (C `)); for A being non empty Subset of (TOP-REAL 2) st U <> V holds
for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let A be non empty Subset of (TOP-REAL 2); ( U <> V implies for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) ) )
assume A1:
U <> V
; for r being positive real number st A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P holds
for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let r be positive real number ; ( A c= C & C c= Ball (p,r) & p in V & (Cl P) /\ (P `) c= A & Ball (p,r) meets P implies for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) ) )
set D = Tdisk (p,r);
assume that
A2:
A c= C
and
A3:
C c= Ball (p,r)
and
A4:
p in V
and
A5:
(Cl P) /\ (P `) c= A
and
A6:
Ball (p,r) meets P
; for f being Function of (Tdisk (p,r)),((TOP-REAL 2) | A) st f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} holds
ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
let f be Function of (Tdisk (p,r)),((TOP-REAL 2) | A); ( f is continuous & f | A = id A & U = P & U is a_component & V is a_component & B = (cl_Ball (p,r)) \ {p} implies ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) ) )
assume that
A7:
f is continuous
and
A8:
f | A = id A
and
A9:
U = P
and
A10:
U is a_component
and
A11:
V is a_component
and
A12:
B = (cl_Ball (p,r)) \ {p}
; ex g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) st
( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
reconsider B1 = B as non empty Subset of (TOP-REAL 2) by A12;
reconsider T2B1 = (TOP-REAL 2) | B1 as non empty SubSpace of TOP-REAL 2 ;
A13:
the carrier of ((TOP-REAL 2) | (C `)) = C `
by PRE_TOPC:29;
A14:
the carrier of ((TOP-REAL 2) | A) = A
by PRE_TOPC:29;
A15:
the carrier of (Tdisk (p,r)) = cl_Ball (p,r)
by BROUWER:3;
A16:
Ball (p,r) c= cl_Ball (p,r)
by TOPREAL9:16;
A17:
not p in C
by A4, A13, XBOOLE_0:def 5;
|.(p - p).| = 0
by TOPRNS_1:29;
then A18:
p in [#] (Tdisk (p,r))
by A15, TOPREAL9:8;
A19:
P c= Cl P
by PRE_TOPC:48;
ex j being set st
( j in Ball (p,r) & j in P )
by A6, XBOOLE_0:3;
then reconsider F1 = (Cl P) /\ ([#] (Tdisk (p,r))) as non empty Subset of (Tdisk (p,r)) by A15, A16, A19, XBOOLE_0:def 4;
then
p in P `
by SUBSET_1:50;
then reconsider F3 = (P `) /\ ([#] (Tdisk (p,r))) as non empty Subset of (Tdisk (p,r)) by A18, XBOOLE_0:def 4;
set T1 = (Tdisk (p,r)) | F1;
set T3 = (Tdisk (p,r)) | F3;
A21:
the carrier of ((Tdisk (p,r)) | F1) = F1
by PRE_TOPC:29;
A22:
the carrier of ((Tdisk (p,r)) | F3) = F3
by PRE_TOPC:29;
A23:
the carrier of ((TOP-REAL 2) | B1) = B1
by PRE_TOPC:29;
A24:
A c= B
A26:
F1 c= B
then reconsider f1 = id F1 as Function of ((Tdisk (p,r)) | F1),T2B1 by A21, A23, FUNCT_2:9;
f | F3 is Function of F3,A
by A14, FUNCT_2:38;
then reconsider g1 = f | F3 as Function of ((Tdisk (p,r)) | F3),T2B1 by A22, A23, A24, FUNCT_2:9;
A30:
F1 = [#] ((Tdisk (p,r)) | F1)
by PRE_TOPC:29;
A31:
F3 = [#] ((Tdisk (p,r)) | F3)
by PRE_TOPC:29;
A32:
([#] ((Tdisk (p,r)) | F1)) \/ ([#] ((Tdisk (p,r)) | F3)) = [#] (Tdisk (p,r))
proof
thus
([#] ((Tdisk (p,r)) | F1)) \/ ([#] ((Tdisk (p,r)) | F3)) c= [#] (Tdisk (p,r))
by A30, A31, XBOOLE_1:8;
XBOOLE_0:def 10 [#] (Tdisk (p,r)) c= ([#] ((Tdisk (p,r)) | F1)) \/ ([#] ((Tdisk (p,r)) | F3))
let p be
set ;
TARSKI:def 3 ( not p in [#] (Tdisk (p,r)) or p in ([#] ((Tdisk (p,r)) | F1)) \/ ([#] ((Tdisk (p,r)) | F3)) )
assume A33:
p in [#] (Tdisk (p,r))
;
p in ([#] ((Tdisk (p,r)) | F1)) \/ ([#] ((Tdisk (p,r)) | F3))
end;
reconsider DT = [#] (Tdisk (p,r)) as closed Subset of (TOP-REAL 2) by BORSUK_1:def 14, TSEP_1:1;
DT /\ (Cl P) is closed
;
then A34:
F1 is closed
by TSEP_1:8;
P is_a_component_of C `
then
P is open
by SPRECT_3:18;
then
DT /\ (P `) is closed
;
then A35:
F3 is closed
by TSEP_1:8;
A36:
id ((Tdisk (p,r)) | F1) = id F1
by PRE_TOPC:29;
(Tdisk (p,r)) | F1 is SubSpace of TOP-REAL 2
by TSEP_1:7;
then
(Tdisk (p,r)) | F1 is SubSpace of T2B1
by A21, A23, A26, TSEP_1:4;
then A37:
f1 is continuous
by A36, PRE_TOPC:56;
A38:
(TOP-REAL 2) | A is SubSpace of T2B1
by A14, A23, A24, TSEP_1:4;
reconsider g2 = g1 as Function of ((Tdisk (p,r)) | F3),((TOP-REAL 2) | A) by A22, FUNCT_2:38;
g2 is continuous
by A7, TOPMETR:10;
then A39:
g1 is continuous
by A38, PRE_TOPC:56;
A40:
for x being set st x in Cl P & x in P ` holds
f . x = x
for x being set st x in ([#] ((Tdisk (p,r)) | F1)) /\ ([#] ((Tdisk (p,r)) | F3)) holds
f1 . x = g1 . x
proof
let x be
set ;
( x in ([#] ((Tdisk (p,r)) | F1)) /\ ([#] ((Tdisk (p,r)) | F3)) implies f1 . x = g1 . x )
assume A44:
x in ([#] ((Tdisk (p,r)) | F1)) /\ ([#] ((Tdisk (p,r)) | F3))
;
f1 . x = g1 . x
then A45:
x in [#] ((Tdisk (p,r)) | F1)
by XBOOLE_0:def 4;
then A46:
x in Cl P
by A30, XBOOLE_0:def 4;
x in P `
by A31, A44, XBOOLE_0:def 4;
then A47:
f . x = x
by A40, A46;
thus f1 . x =
x
by A30, A45, FUNCT_1:35
.=
g1 . x
by A31, A44, A47, FUNCT_1:72
;
verum
end;
then consider g being Function of (Tdisk (p,r)),((TOP-REAL 2) | B) such that
A48:
g = f1 +* g1
and
A49:
g is continuous
by A30, A31, A32, A34, A35, A37, A39, JGRAPH_2:9;
take
g
; ( g is continuous & ( for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) ) ) )
thus
g is continuous
by A49; for x being Point of (Tdisk (p,r)) holds
( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) )
let x be Point of (Tdisk (p,r)); ( ( x in Cl P implies g . x = x ) & ( x in P ` implies g . x = f . x ) )
A50:
dom g1 = the carrier of ((Tdisk (p,r)) | F3)
by FUNCT_2:def 1;
hereby ( x in P ` implies g . x = f . x )
end;
assume
x in P `
; g . x = f . x
then A55:
x in F3
by XBOOLE_0:def 4;
hence g . x =
g1 . x
by A22, A48, A50, FUNCT_4:14
.=
f . x
by A55, FUNCT_1:72
;
verum