let X be set ; :: thesis: for L, S being non empty RelStr st RelStr(# the carrier of L, the InternalRel of L #) = RelStr(# the carrier of S, the InternalRel of S #) holds
L |^ X = S |^ X

let L, S be non empty RelStr ; :: thesis: ( RelStr(# the carrier of L, the InternalRel of L #) = RelStr(# the carrier of S, the InternalRel of S #) implies L |^ X = S |^ X )
assume A1: RelStr(# the carrier of L, the InternalRel of L #) = RelStr(# the carrier of S, the InternalRel of S #) ; :: thesis: L |^ X = S |^ X
reconsider tXL = X --> L as RelStr-yielding ManySortedSet of X ;
reconsider tXS = X --> S as RelStr-yielding ManySortedSet of X ;
A2: for x being object st x in dom (Carrier tXS) holds
(Carrier tXS) . x = (Carrier tXL) . x
proof
let x be object ; :: thesis: ( x in dom (Carrier tXS) implies (Carrier tXS) . x = (Carrier tXL) . x )
assume x in dom (Carrier tXS) ; :: thesis: (Carrier tXS) . x = (Carrier tXL) . x
then A3: x in X ;
then A4: ex R1 being 1-sorted st
( tXL . x = R1 & (Carrier tXL) . x = the carrier of R1 ) by PRALG_1:def 15;
ex R being 1-sorted st
( tXS . x = R & (Carrier tXS) . x = the carrier of R ) by A3, PRALG_1:def 15;
hence (Carrier tXS) . x = the carrier of S by A3, FUNCOP_1:7
.= (Carrier tXL) . x by A1, A3, A4, FUNCOP_1:7 ;
:: thesis: verum
end;
A5: dom (Carrier tXS) = X by PARTFUN1:def 2
.= dom (Carrier tXL) by PARTFUN1:def 2 ;
A6: the carrier of (S |^ X) = the carrier of (product tXS) by YELLOW_1:def 5
.= product (Carrier tXS) by YELLOW_1:def 4
.= product (Carrier tXL) by A5, A2, FUNCT_1:2
.= the carrier of (product tXL) by YELLOW_1:def 4
.= the carrier of (L |^ X) by YELLOW_1:def 5 ;
A7: the InternalRel of (L |^ X) c= the InternalRel of (S |^ X)
proof
reconsider tXS = X --> S as RelStr-yielding ManySortedSet of X ;
reconsider tXL = X --> L as RelStr-yielding ManySortedSet of X ;
let x be object ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (L |^ X) or x in the InternalRel of (S |^ X) )
assume A8: x in the InternalRel of (L |^ X) ; :: thesis: x in the InternalRel of (S |^ X)
then consider a, b being object such that
A9: x = [a,b] and
A10: a in the carrier of (L |^ X) and
A11: b in the carrier of (L |^ X) by RELSET_1:2;
reconsider a = a, b = b as Element of (L |^ X) by A10, A11;
A12: L |^ X = product tXL by YELLOW_1:def 5;
then A13: the carrier of (L |^ X) = product (Carrier tXL) by YELLOW_1:def 4;
a <= b by A8, A9, ORDERS_2:def 5;
then consider f, g being Function such that
A14: f = a and
A15: g = b and
A16: for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi ) by A12, A13, YELLOW_1:def 4;
reconsider a1 = a, b1 = b as Element of (S |^ X) by A6;
A17: ex f, g being Function st
( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi ) ) )
proof
take f ; :: thesis: ex g being Function st
( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi ) ) )

take g ; :: thesis: ( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi ) ) )

thus ( f = a1 & g = b1 ) by A14, A15; :: thesis: for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi )

let i be object ; :: thesis: ( i in X implies ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi ) )

assume A18: i in X ; :: thesis: ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi )

then consider R being RelStr , xi, yi being Element of R such that
A19: R = tXL . i and
A20: xi = f . i and
A21: yi = g . i and
A22: xi <= yi by A16;
take R1 = S; :: thesis: ex xi, yi being Element of R1 st
( R1 = tXS . i & xi = f . i & yi = g . i & xi <= yi )

reconsider xi1 = xi, yi1 = yi as Element of R1 by A1, A18, A19, FUNCOP_1:7;
take xi1 ; :: thesis: ex yi being Element of R1 st
( R1 = tXS . i & xi1 = f . i & yi = g . i & xi1 <= yi )

take yi1 ; :: thesis: ( R1 = tXS . i & xi1 = f . i & yi1 = g . i & xi1 <= yi1 )
thus R1 = tXS . i by A18, FUNCOP_1:7; :: thesis: ( xi1 = f . i & yi1 = g . i & xi1 <= yi1 )
thus ( xi1 = f . i & yi1 = g . i ) by A20, A21; :: thesis: xi1 <= yi1
the InternalRel of R = the InternalRel of L by A18, A19, FUNCOP_1:7;
then [xi1,yi1] in the InternalRel of R1 by A1, A22, ORDERS_2:def 5;
hence xi1 <= yi1 by ORDERS_2:def 5; :: thesis: verum
end;
A23: S |^ X = product tXS by YELLOW_1:def 5;
then the carrier of (S |^ X) = product (Carrier tXS) by YELLOW_1:def 4;
then a1 <= b1 by A17, A23, YELLOW_1:def 4;
hence x in the InternalRel of (S |^ X) by A9, ORDERS_2:def 5; :: thesis: verum
end;
the InternalRel of (S |^ X) c= the InternalRel of (L |^ X)
proof
reconsider tXL = X --> L as RelStr-yielding ManySortedSet of X ;
reconsider tXS = X --> S as RelStr-yielding ManySortedSet of X ;
let x be object ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (S |^ X) or x in the InternalRel of (L |^ X) )
assume A24: x in the InternalRel of (S |^ X) ; :: thesis: x in the InternalRel of (L |^ X)
then consider a, b being object such that
A25: x = [a,b] and
A26: a in the carrier of (S |^ X) and
A27: b in the carrier of (S |^ X) by RELSET_1:2;
reconsider a = a, b = b as Element of (S |^ X) by A26, A27;
A28: S |^ X = product tXS by YELLOW_1:def 5;
then A29: the carrier of (S |^ X) = product (Carrier tXS) by YELLOW_1:def 4;
a <= b by A24, A25, ORDERS_2:def 5;
then consider f, g being Function such that
A30: f = a and
A31: g = b and
A32: for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXS . i & xi = f . i & yi = g . i & xi <= yi ) by A28, A29, YELLOW_1:def 4;
reconsider a1 = a, b1 = b as Element of (L |^ X) by A6;
A33: ex f, g being Function st
( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi ) ) )
proof
take f ; :: thesis: ex g being Function st
( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi ) ) )

take g ; :: thesis: ( f = a1 & g = b1 & ( for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi ) ) )

thus ( f = a1 & g = b1 ) by A30, A31; :: thesis: for i being object st i in X holds
ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi )

let i be object ; :: thesis: ( i in X implies ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi ) )

assume A34: i in X ; :: thesis: ex R being RelStr ex xi, yi being Element of R st
( R = tXL . i & xi = f . i & yi = g . i & xi <= yi )

then consider R being RelStr , xi, yi being Element of R such that
A35: R = tXS . i and
A36: xi = f . i and
A37: yi = g . i and
A38: xi <= yi by A32;
take R1 = L; :: thesis: ex xi, yi being Element of R1 st
( R1 = tXL . i & xi = f . i & yi = g . i & xi <= yi )

reconsider xi1 = xi, yi1 = yi as Element of R1 by A1, A34, A35, FUNCOP_1:7;
take xi1 ; :: thesis: ex yi being Element of R1 st
( R1 = tXL . i & xi1 = f . i & yi = g . i & xi1 <= yi )

take yi1 ; :: thesis: ( R1 = tXL . i & xi1 = f . i & yi1 = g . i & xi1 <= yi1 )
thus R1 = tXL . i by A34, FUNCOP_1:7; :: thesis: ( xi1 = f . i & yi1 = g . i & xi1 <= yi1 )
thus ( xi1 = f . i & yi1 = g . i ) by A36, A37; :: thesis: xi1 <= yi1
the InternalRel of R = the InternalRel of S by A34, A35, FUNCOP_1:7;
then [xi1,yi1] in the InternalRel of R1 by A1, A38, ORDERS_2:def 5;
hence xi1 <= yi1 by ORDERS_2:def 5; :: thesis: verum
end;
A39: L |^ X = product tXL by YELLOW_1:def 5;
then the carrier of (L |^ X) = product (Carrier tXL) by YELLOW_1:def 4;
then a1 <= b1 by A33, A39, YELLOW_1:def 4;
hence x in the InternalRel of (L |^ X) by A25, ORDERS_2:def 5; :: thesis: verum
end;
hence L |^ X = S |^ X by A7, A6, XBOOLE_0:def 10; :: thesis: verum