let G1, G2 be RelStr ; ( the carrier of G1 misses the carrier of G2 implies ComplRelStr (union_of G1,G2) = sum_of (ComplRelStr G1),(ComplRelStr G2) )
A1: the carrier of (sum_of (ComplRelStr G1),(ComplRelStr G2)) =
the carrier of (ComplRelStr G1) \/ the carrier of (ComplRelStr G2)
by NECKLA_2:def 3
.=
the carrier of G1 \/ the carrier of (ComplRelStr G2)
by NECKLACE:def 9
.=
the carrier of G1 \/ the carrier of G2
by NECKLACE:def 9
;
set P = the InternalRel of (ComplRelStr (union_of G1,G2));
set R = the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2));
set X1 = the InternalRel of (ComplRelStr G1);
set X2 = the InternalRel of (ComplRelStr G2);
set X3 = [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):];
set X4 = [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):];
set X5 = [:the carrier of G1,the carrier of G1:];
set X6 = [:the carrier of G2,the carrier of G2:];
set X7 = [:the carrier of G1,the carrier of G2:];
set X8 = [:the carrier of G2,the carrier of G1:];
assume A2:
the carrier of G1 misses the carrier of G2
; ComplRelStr (union_of G1,G2) = sum_of (ComplRelStr G1),(ComplRelStr G2)
A3:
for a, b being set holds
( [a,b] in the InternalRel of (ComplRelStr (union_of G1,G2)) iff [a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2)) )
proof
let a,
b be
set ;
( [a,b] in the InternalRel of (ComplRelStr (union_of G1,G2)) iff [a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2)) )
set x =
[a,b];
thus
(
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2)) implies
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2)) )
( [a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2)) implies [a,b] in the InternalRel of (ComplRelStr (union_of G1,G2)) )proof
assume
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2))
;
[a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2))
then A4:
[a,b] in (the InternalRel of (union_of G1,G2) ` ) \ (id the carrier of (union_of G1,G2))
by NECKLACE:def 9;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):]
;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then A5:
[a,b] in [:(the carrier of G1 \/ the carrier of G2),(the carrier of G1 \/ the carrier of G2):]
by NECKLA_2:def 2;
not
[a,b] in id the
carrier of
(union_of G1,G2)
by A4, XBOOLE_0:def 5;
then A6:
not
[a,b] in id (the carrier of G1 \/ the carrier of G2)
by NECKLA_2:def 2;
A7:
( not
[a,b] in id the
carrier of
G1 & not
[a,b] in id the
carrier of
G2 )
( the
carrier of
G1 = the
carrier of
(ComplRelStr G1) & the
carrier of
G2 = the
carrier of
(ComplRelStr G2) )
by NECKLACE:def 9;
then
[a,b] in (([:the carrier of G1,the carrier of G1:] \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]) \/ [:the carrier of G2,the carrier of G2:]
by A5, ZFMISC_1:121;
then
[a,b] in [:the carrier of G1,the carrier of G1:] \/ (([:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]) \/ [:the carrier of G2,the carrier of G2:])
by XBOOLE_1:113;
then
(
[a,b] in [:the carrier of G1,the carrier of G1:] or
[a,b] in ([:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]) \/ [:the carrier of G2,the carrier of G2:] )
by XBOOLE_0:def 3;
then
(
[a,b] in [:the carrier of G1,the carrier of G1:] or
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] \/ ([:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] \/ [:the carrier of G2,the carrier of G2:]) )
by XBOOLE_1:4;
then A8:
(
[a,b] in [:the carrier of G1,the carrier of G1:] or
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] or
[a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] \/ [:the carrier of G2,the carrier of G2:] )
by XBOOLE_0:def 3;
[a,b] in the
InternalRel of
(union_of G1,G2) `
by A4, XBOOLE_0:def 5;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):] \ the
InternalRel of
(union_of G1,G2)
by SUBSET_1:def 5;
then
not
[a,b] in the
InternalRel of
(union_of G1,G2)
by XBOOLE_0:def 5;
then A9:
not
[a,b] in the
InternalRel of
G1 \/ the
InternalRel of
G2
by NECKLA_2:def 2;
then A10:
not
[a,b] in the
InternalRel of
G1
by XBOOLE_0:def 3;
A11:
not
[a,b] in the
InternalRel of
G2
by A9, XBOOLE_0:def 3;
per cases
( [a,b] in [:the carrier of G1,the carrier of G1:] or [a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] or [a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] or [a,b] in [:the carrier of G2,the carrier of G2:] )
by A8, XBOOLE_0:def 3;
suppose
[a,b] in [:the carrier of G1,the carrier of G1:]
;
[a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2))then
[a,b] in [:the carrier of G1,the carrier of G1:] \ the
InternalRel of
G1
by A10, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
G1 `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of G1 ` ) \ (id the carrier of G1)
by A7, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(ComplRelStr G1)
by NECKLACE:def 9;
then
[a,b] in the
InternalRel of
(ComplRelStr G1) \/ ((the InternalRel of (ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):])
by XBOOLE_0:def 3;
then
[a,b] in ((the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_1:113;
hence
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2))
by NECKLA_2:def 3;
verum end; suppose
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]
;
[a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2))then
[a,b] in the
InternalRel of
(ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]
by XBOOLE_0:def 3;
then
[a,b] in (the InternalRel of (ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_0:def 3;
then
[a,b] in the
InternalRel of
(ComplRelStr G1) \/ ((the InternalRel of (ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):])
by XBOOLE_0:def 3;
then
[a,b] in ((the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_1:113;
hence
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2))
by NECKLA_2:def 3;
verum end; suppose
[a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
;
[a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2))then
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_0:def 3;
then
[a,b] in the
InternalRel of
(ComplRelStr G2) \/ ([:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):])
by XBOOLE_0:def 3;
then
[a,b] in (the InternalRel of (ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_1:4;
then
[a,b] in the
InternalRel of
(ComplRelStr G1) \/ ((the InternalRel of (ComplRelStr G2) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):])
by XBOOLE_0:def 3;
then
[a,b] in ((the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_1:113;
hence
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2))
by NECKLA_2:def 3;
verum end; suppose
[a,b] in [:the carrier of G2,the carrier of G2:]
;
[a,b] in the InternalRel of (sum_of (ComplRelStr G1),(ComplRelStr G2))then
[a,b] in [:the carrier of G2,the carrier of G2:] \ the
InternalRel of
G2
by A11, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
G2 `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of G2 ` ) \ (id the carrier of G2)
by A7, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(ComplRelStr G2)
by NECKLACE:def 9;
then
[a,b] in the
InternalRel of
(ComplRelStr G1) \/ the
InternalRel of
(ComplRelStr G2)
by XBOOLE_0:def 3;
then
[a,b] in (the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]
by XBOOLE_0:def 3;
then
[a,b] in ((the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by XBOOLE_0:def 3;
hence
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2))
by NECKLA_2:def 3;
verum end; end;
end;
assume
[a,b] in the
InternalRel of
(sum_of (ComplRelStr G1),(ComplRelStr G2))
;
[a,b] in the InternalRel of (ComplRelStr (union_of G1,G2))
then
[a,b] in ((the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]) \/ [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
by NECKLA_2:def 3;
then
(
[a,b] in (the InternalRel of (ComplRelStr G1) \/ the InternalRel of (ComplRelStr G2)) \/ [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] or
[a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] )
by XBOOLE_0:def 3;
then A12:
(
[a,b] in the
InternalRel of
(ComplRelStr G1) \/ the
InternalRel of
(ComplRelStr G2) or
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] or
[a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] )
by XBOOLE_0:def 3;
per cases
( [a,b] in the InternalRel of (ComplRelStr G1) or [a,b] in the InternalRel of (ComplRelStr G2) or [a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):] or [a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):] )
by A12, XBOOLE_0:def 3;
suppose
[a,b] in the
InternalRel of
(ComplRelStr G1)
;
[a,b] in the InternalRel of (ComplRelStr (union_of G1,G2))then A13:
[a,b] in (the InternalRel of G1 ` ) \ (id the carrier of G1)
by NECKLACE:def 9;
then
[a,b] in the
InternalRel of
G1 `
by XBOOLE_0:def 5;
then
[a,b] in [:the carrier of G1,the carrier of G1:] \ the
InternalRel of
G1
by SUBSET_1:def 5;
then A14:
not
[a,b] in the
InternalRel of
G1
by XBOOLE_0:def 5;
A15:
not
[a,b] in the
InternalRel of
(union_of G1,G2)
proof
assume
[a,b] in the
InternalRel of
(union_of G1,G2)
;
contradiction
then
[a,b] in the
InternalRel of
G1 \/ the
InternalRel of
G2
by NECKLA_2:def 2;
then
[a,b] in the
InternalRel of
G2
by A14, XBOOLE_0:def 3;
then
not
[:the carrier of G1,the carrier of G1:] /\ [:the carrier of G2,the carrier of G2:] is
empty
by A13, XBOOLE_0:def 4;
then
[:the carrier of G1,the carrier of G1:] meets [:the carrier of G2,the carrier of G2:]
by XBOOLE_0:def 7;
hence
contradiction
by A2, ZFMISC_1:127;
verum
end; A16:
not
[a,b] in id the
carrier of
(union_of G1,G2)
[a,b] in [:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]
by A13, XBOOLE_0:def 3;
then
[a,b] in ([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]
by XBOOLE_0:def 3;
then
[a,b] in (([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:]
by XBOOLE_0:def 3;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),(the carrier of G1 \/ the carrier of G2):]
by ZFMISC_1:121;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):] \ the
InternalRel of
(union_of G1,G2)
by A15, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(union_of G1,G2) `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of (union_of G1,G2) ` ) \ (id the carrier of (union_of G1,G2))
by A16, XBOOLE_0:def 5;
hence
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2))
by NECKLACE:def 9;
verum end; suppose
[a,b] in the
InternalRel of
(ComplRelStr G2)
;
[a,b] in the InternalRel of (ComplRelStr (union_of G1,G2))then A18:
[a,b] in (the InternalRel of G2 ` ) \ (id the carrier of G2)
by NECKLACE:def 9;
then
[a,b] in the
InternalRel of
G2 `
by XBOOLE_0:def 5;
then
[a,b] in [:the carrier of G2,the carrier of G2:] \ the
InternalRel of
G2
by SUBSET_1:def 5;
then A19:
not
[a,b] in the
InternalRel of
G2
by XBOOLE_0:def 5;
A20:
not
[a,b] in the
InternalRel of
(union_of G1,G2)
proof
assume
[a,b] in the
InternalRel of
(union_of G1,G2)
;
contradiction
then
[a,b] in the
InternalRel of
G1 \/ the
InternalRel of
G2
by NECKLA_2:def 2;
then
[a,b] in the
InternalRel of
G1
by A19, XBOOLE_0:def 3;
then
not
[:the carrier of G1,the carrier of G1:] /\ [:the carrier of G2,the carrier of G2:] is
empty
by A18, XBOOLE_0:def 4;
then
[:the carrier of G1,the carrier of G1:] meets [:the carrier of G2,the carrier of G2:]
by XBOOLE_0:def 7;
hence
contradiction
by A2, ZFMISC_1:127;
verum
end; A21:
not
[a,b] in id the
carrier of
(union_of G1,G2)
[a,b] in [:the carrier of G2,the carrier of G1:] \/ [:the carrier of G2,the carrier of G2:]
by A18, XBOOLE_0:def 3;
then
[a,b] in [:the carrier of G1,the carrier of G2:] \/ ([:the carrier of G2,the carrier of G1:] \/ [:the carrier of G2,the carrier of G2:])
by XBOOLE_0:def 3;
then
[a,b] in ([:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:]
by XBOOLE_1:4;
then
[a,b] in [:the carrier of G1,the carrier of G1:] \/ (([:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:])
by XBOOLE_0:def 3;
then
[a,b] in (([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:]
by XBOOLE_1:113;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),(the carrier of G1 \/ the carrier of G2):]
by ZFMISC_1:121;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):] \ the
InternalRel of
(union_of G1,G2)
by A20, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(union_of G1,G2) `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of (union_of G1,G2) ` ) \ (id the carrier of (union_of G1,G2))
by A21, XBOOLE_0:def 5;
hence
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2))
by NECKLACE:def 9;
verum end; suppose
[a,b] in [:the carrier of (ComplRelStr G1),the carrier of (ComplRelStr G2):]
;
[a,b] in the InternalRel of (ComplRelStr (union_of G1,G2))then A23:
[a,b] in [:the carrier of G1,the carrier of (ComplRelStr G2):]
by NECKLACE:def 9;
then A24:
[a,b] in [:the carrier of G1,the carrier of G2:]
by NECKLACE:def 9;
A25:
not
[a,b] in the
InternalRel of
(union_of G1,G2)
A31:
not
[a,b] in id the
carrier of
(union_of G1,G2)
[a,b] in [:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:]
by A24, XBOOLE_0:def 3;
then
[a,b] in [:the carrier of G1,the carrier of G1:] \/ ([:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:])
by XBOOLE_0:def 3;
then
[a,b] in ([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]
by XBOOLE_1:4;
then
[a,b] in (([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:]
by XBOOLE_0:def 3;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),(the carrier of G1 \/ the carrier of G2):]
by ZFMISC_1:121;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):] \ the
InternalRel of
(union_of G1,G2)
by A25, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(union_of G1,G2) `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of (union_of G1,G2) ` ) \ (id the carrier of (union_of G1,G2))
by A31, XBOOLE_0:def 5;
hence
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2))
by NECKLACE:def 9;
verum end; suppose
[a,b] in [:the carrier of (ComplRelStr G2),the carrier of (ComplRelStr G1):]
;
[a,b] in the InternalRel of (ComplRelStr (union_of G1,G2))then A37:
[a,b] in [:the carrier of G2,the carrier of (ComplRelStr G1):]
by NECKLACE:def 9;
then A38:
[a,b] in [:the carrier of G2,the carrier of G1:]
by NECKLACE:def 9;
A39:
not
[a,b] in the
InternalRel of
(union_of G1,G2)
A45:
not
[a,b] in id the
carrier of
(union_of G1,G2)
[a,b] in [:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:]
by A38, XBOOLE_0:def 3;
then
[a,b] in [:the carrier of G1,the carrier of G1:] \/ ([:the carrier of G1,the carrier of G2:] \/ [:the carrier of G2,the carrier of G1:])
by XBOOLE_0:def 3;
then
[a,b] in ([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]
by XBOOLE_1:4;
then
[a,b] in (([:the carrier of G1,the carrier of G1:] \/ [:the carrier of G1,the carrier of G2:]) \/ [:the carrier of G2,the carrier of G1:]) \/ [:the carrier of G2,the carrier of G2:]
by XBOOLE_0:def 3;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),(the carrier of G1 \/ the carrier of G2):]
by ZFMISC_1:121;
then
[a,b] in [:(the carrier of G1 \/ the carrier of G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):]
by NECKLA_2:def 2;
then
[a,b] in [:the carrier of (union_of G1,G2),the carrier of (union_of G1,G2):] \ the
InternalRel of
(union_of G1,G2)
by A39, XBOOLE_0:def 5;
then
[a,b] in the
InternalRel of
(union_of G1,G2) `
by SUBSET_1:def 5;
then
[a,b] in (the InternalRel of (union_of G1,G2) ` ) \ (id the carrier of (union_of G1,G2))
by A45, XBOOLE_0:def 5;
hence
[a,b] in the
InternalRel of
(ComplRelStr (union_of G1,G2))
by NECKLACE:def 9;
verum end; end;
end;
the carrier of (ComplRelStr (union_of G1,G2)) =
the carrier of (union_of G1,G2)
by NECKLACE:def 9
.=
the carrier of G1 \/ the carrier of G2
by NECKLA_2:def 2
;
hence
ComplRelStr (union_of G1,G2) = sum_of (ComplRelStr G1),(ComplRelStr G2)
by A1, A3, RELAT_1:def 2; verum