A1: dom J = I by PARTFUN1:def 2;
defpred S1[ Function, Function] means for i being Element of I holds $1 . i = $2 | (J . i);
A2: for x being Element of (dprod F) ex y being Element of (product (Union F)) st S1[x,y]
proof
let x be Element of (dprod F); :: thesis: ex y being Element of (product (Union F)) st S1[x,y]
A3: x in product (prod_bundle F) ;
A4: dom x = I by GROUP_19:3;
A5: for i being Element of I holds x . i in product (F . i)
proof
let i be Element of I; :: thesis: x . i in product (F . i)
x . i in (prod_bundle F) . i by A3, GROUP_19:5;
hence x . i in product (F . i) by Def6; :: thesis: verum
end;
set y = Union x;
for z being object st z in Union x holds
ex a, b being object st z = [a,b]
proof
let z be object ; :: thesis: ( z in Union x implies ex a, b being object st z = [a,b] )
assume z in Union x ; :: thesis: ex a, b being object st z = [a,b]
then consider Y being set such that
A6: ( z in Y & Y in rng x ) by TARSKI:def 4;
consider i being object such that
A7: ( i in dom x & Y = x . i ) by A6, FUNCT_1:def 3;
reconsider i = i as Element of I by A7, GROUP_19:3;
x . i in product (F . i) by A5;
hence ex a, b being object st z = [a,b] by A6, A7, RELAT_1:def 1; :: thesis: verum
end;
then Union x is Relation-like ;
then reconsider y = Union x as Relation ;
for a, b1, b2 being object st [a,b1] in y & [a,b2] in y holds
b1 = b2
proof
let a, b1, b2 be object ; :: thesis: ( [a,b1] in y & [a,b2] in y implies b1 = b2 )
assume A8: ( [a,b1] in y & [a,b2] in y ) ; :: thesis: b1 = b2
then consider Y1 being set such that
A9: ( [a,b1] in Y1 & Y1 in rng x ) by TARSKI:def 4;
consider i1 being object such that
A10: ( i1 in dom x & Y1 = x . i1 ) by A9, FUNCT_1:def 3;
reconsider i1 = i1 as Element of I by A10, GROUP_19:3;
A11: x . i1 in product (F . i1) by A5;
reconsider xi1 = x . i1 as Function by A11;
A12: a in dom xi1 by A9, A10, FUNCT_1:1;
A13: a in J . i1 by A11, A12, GROUP_19:3;
consider Y2 being set such that
A14: ( [a,b2] in Y2 & Y2 in rng x ) by A8, TARSKI:def 4;
consider i2 being object such that
A15: ( i2 in dom x & Y2 = x . i2 ) by A14, FUNCT_1:def 3;
reconsider i2 = i2 as Element of I by A15, GROUP_19:3;
A16: x . i2 in product (F . i2) by A5;
reconsider xi2 = x . i2 as Function by A16;
A17: a in dom xi2 by A14, A15, FUNCT_1:1;
a in J . i2 by A16, A17, GROUP_19:3;
then A18: (J . i1) /\ (J . i2) <> {} by A13, XBOOLE_0:def 4;
i1 = i2 by A18, PROB_2:def 2, XBOOLE_0:def 7;
hence b1 = b2 by A9, A10, A11, A14, A15, FUNCT_1:def 1; :: thesis: verum
end;
then y is Function-like ;
then reconsider y = y as Function ;
A19: for a being object holds
( a in dom y iff a in Union J )
proof
let a be object ; :: thesis: ( a in dom y iff a in Union J )
hereby :: thesis: ( a in Union J implies a in dom y )
assume a in dom y ; :: thesis: a in Union J
then consider b being object such that
A20: [a,b] in y by XTUPLE_0:def 12;
consider Y being set such that
A21: ( [a,b] in Y & Y in rng x ) by A20, TARSKI:def 4;
consider i being object such that
A22: ( i in dom x & Y = x . i ) by A21, FUNCT_1:def 3;
reconsider i = i as Element of I by A22, GROUP_19:3;
A23: x . i in product (F . i) by A5;
then reconsider xi = x . i as Function ;
A24: a in dom xi by A21, A22, FUNCT_1:1;
( a in J . i & J . i in rng J ) by A1, A23, A24, FUNCT_1:3, GROUP_19:3;
hence a in Union J by TARSKI:def 4; :: thesis: verum
end;
assume a in Union J ; :: thesis: a in dom y
then consider Y being set such that
A25: ( a in Y & Y in rng J ) by TARSKI:def 4;
consider i being object such that
A26: ( i in dom J & Y = J . i ) by A25, FUNCT_1:def 3;
reconsider i = i as Element of I by A26;
A27: x . i in product (F . i) by A5;
reconsider xi = x . i as Function by A27;
a in dom xi by A25, A26, A27, GROUP_19:3;
then consider b being object such that
A28: [a,b] in xi by XTUPLE_0:def 12;
xi in rng x by A4, FUNCT_1:3;
then [a,b] in y by A28, TARSKI:def 4;
hence a in dom y by XTUPLE_0:def 12; :: thesis: verum
end;
then A29: dom y = Union J by TARSKI:2;
then reconsider y = y as ManySortedSet of Union J by PARTFUN1:def 2, RELAT_1:def 18;
reconsider z = Carrier (Union F) as ManySortedSet of Union J ;
A30: dom z = Union J by PARTFUN1:def 2;
for i being object st i in Union J holds
y . i in z . i
proof
let i be object ; :: thesis: ( i in Union J implies y . i in z . i )
assume i in Union J ; :: thesis: y . i in z . i
then reconsider i = i as Element of Union J ;
[i,(y . i)] in y by A19, FUNCT_1:1;
then consider Yi being set such that
A31: ( [i,(y . i)] in Yi & Yi in rng x ) by TARSKI:def 4;
consider j being object such that
A32: ( j in dom x & Yi = x . j ) by A31, FUNCT_1:def 3;
reconsider j = j as Element of I by A32, GROUP_19:3;
A33: x . j in product (F . j) by A5;
reconsider xj = x . j as Function by A33;
A34: ( i in dom xj & y . i = xj . i ) by A31, A32, FUNCT_1:1;
A35: i in J . j by A33, A34, GROUP_19:3;
dom (Union F) = Union J by PARTFUN1:def 2;
then [i,((Union F) . i)] in Union F by FUNCT_1:1;
then consider Y0 being set such that
A36: ( [i,((Union F) . i)] in Y0 & Y0 in rng F ) by TARSKI:def 4;
consider k being object such that
A37: ( k in dom F & Y0 = F . k ) by A36, FUNCT_1:def 3;
reconsider k = k as Element of I by A37;
reconsider Fk = F . k as Function ;
A38: dom Fk = J . k by PARTFUN1:def 2;
i in dom Fk by A36, A37, XTUPLE_0:def 12;
then A39: (J . k) /\ (J . j) <> {} by A35, A38, XBOOLE_0:def 4;
reconsider P = (F . j) . i as Group by A35, GROUP_19:1;
j = k by A39, PROB_2:def 2, XBOOLE_0:def 7;
then A40: [#] P = [#] ((Union F) . i) by A36, A37, FUNCT_1:1;
xj . i in P by A33, A35, GROUP_19:5;
hence y . i in z . i by A34, A40, PENCIL_3:7; :: thesis: verum
end;
then y in product z by A29, A30, CARD_3:def 5;
then reconsider y = y as Element of (product (Union F)) by GROUP_7:def 2;
take y ; :: thesis: S1[x,y]
thus for i being Element of I holds x . i = y | (J . i) :: thesis: verum
proof
let i be Element of I; :: thesis: x . i = y | (J . i)
A41: J . i c= Union J by A1, FUNCT_1:3, ZFMISC_1:74;
then A42: dom (y | (J . i)) = J . i by A29, RELAT_1:62;
A43: x . i in product (F . i) by A5;
then reconsider xi = x . i as Function ;
for j being object st j in dom xi holds
xi . j = (y | (J . i)) . j
proof
let j be object ; :: thesis: ( j in dom xi implies xi . j = (y | (J . i)) . j )
assume j in dom xi ; :: thesis: xi . j = (y | (J . i)) . j
then A44: j in J . i by A43, GROUP_19:3;
then A45: (y | (J . i)) . j = y . j by FUNCT_1:49;
j in dom (y | (J . i)) by A29, A41, A44, RELAT_1:62;
then j in (dom y) /\ (J . i) by RELAT_1:61;
then j in dom y by XBOOLE_0:def 4;
then [j,(y . j)] in y by FUNCT_1:1;
then consider Y0 being set such that
A46: ( [j,(y . j)] in Y0 & Y0 in rng x ) by TARSKI:def 4;
consider k being object such that
A47: ( k in dom x & Y0 = x . k ) by A46, FUNCT_1:def 3;
reconsider k = k as Element of I by A47, GROUP_19:3;
A48: x . k in product (F . k) by A5;
then reconsider xk = x . k as Function ;
A49: dom xk = J . k by A48, GROUP_19:3;
j in dom xk by A46, A47, XTUPLE_0:def 12;
then A50: (J . k) /\ (J . i) <> {} by A44, A49, XBOOLE_0:def 4;
i = k by A50, PROB_2:def 2, XBOOLE_0:def 7;
hence xi . j = (y | (J . i)) . j by A45, A46, A47, FUNCT_1:1; :: thesis: verum
end;
hence x . i = y | (J . i) by A42, A43, FUNCT_1:2, GROUP_19:3; :: thesis: verum
end;
end;
consider f being Function of (dprod F),(product (Union F)) such that
A51: for x being Element of (dprod F) holds S1[x,f . x] from FUNCT_2:sch 3(A2);
for a, b being Element of (dprod F) holds f . (a * b) = (f . a) * (f . b)
proof
let a, b be Element of (dprod F); :: thesis: f . (a * b) = (f . a) * (f . b)
reconsider fa = f . a as Element of (product (Union F)) ;
reconsider fb = f . b as Element of (product (Union F)) ;
set fafb = fa * fb;
reconsider fab = f . (a * b) as Element of (product (Union F)) ;
A52: ( a in product (prod_bundle F) & b in product (prod_bundle F) & a * b in product (prod_bundle F) ) ;
A53: for i being Element of I holds
( a . i in product (F . i) & b . i in product (F . i) & (a * b) . i in product (F . i) )
proof
let i be Element of I; :: thesis: ( a . i in product (F . i) & b . i in product (F . i) & (a * b) . i in product (F . i) )
( a . i in (prod_bundle F) . i & b . i in (prod_bundle F) . i & (a * b) . i in (prod_bundle F) . i ) by A52, GROUP_19:5;
hence ( a . i in product (F . i) & b . i in product (F . i) & (a * b) . i in product (F . i) ) by Def6; :: thesis: verum
end;
A54: dom fab = Union J by GROUP_19:3;
for j being object st j in dom fab holds
fab . j = (fa * fb) . j
proof
let j be object ; :: thesis: ( j in dom fab implies fab . j = (fa * fb) . j )
assume A55: j in dom fab ; :: thesis: fab . j = (fa * fb) . j
then consider Y being set such that
A56: ( j in Y & Y in rng J ) by A54, TARSKI:def 4;
consider i being object such that
A57: ( i in dom J & Y = J . i ) by A56, FUNCT_1:def 3;
reconsider i = i as Element of I by A57;
A58: a . i = (f . a) | (J . i) by A51;
A59: b . i = (f . b) | (J . i) by A51;
( a . i in product (F . i) & b . i in product (F . i) & (a * b) . i in product (F . i) ) by A53;
then reconsider ai = a . i, bi = b . i, abi = (a * b) . i as Element of (product (F . i)) ;
reconsider P = (F . i) . j as Group by A56, A57, GROUP_19:1;
ai . j in P by A53, A56, A57, GROUP_19:5;
then reconsider aij = ai . j as Element of P ;
bi . j in P by A53, A56, A57, GROUP_19:5;
then reconsider bij = bi . j as Element of P ;
A60: aij = fa . j by A56, A57, A58, FUNCT_1:49;
then reconsider faj = fa . j as Element of P ;
bij = fb . j by A56, A57, A59, FUNCT_1:49;
then reconsider fbj = fb . j as Element of P ;
(prod_bundle F) . i = product (F . i) by Def6;
then A61: abi . j = (ai * bi) . j by GROUP_7:1
.= aij * bij by A56, A57, GROUP_7:1 ;
A62: j in Union J by A55, GROUP_19:3;
dom (Union F) = Union J by PARTFUN1:def 2;
then [j,((Union F) . j)] in Union F by A62, FUNCT_1:1;
then consider Y0 being set such that
A63: ( [j,((Union F) . j)] in Y0 & Y0 in rng F ) by TARSKI:def 4;
consider k being object such that
A64: ( k in dom F & Y0 = F . k ) by A63, FUNCT_1:def 3;
reconsider k = k as Element of I by A64;
reconsider Fk = F . k as Function ;
j in dom Fk by A63, A64, XTUPLE_0:def 12;
then j in J . k by PARTFUN1:def 2;
then A65: (J . k) /\ (J . i) <> {} by A56, A57, XBOOLE_0:def 4;
i = k by A65, PROB_2:def 2, XBOOLE_0:def 7;
then A66: (Union F) . j = (F . i) . j by A63, A64, FUNCT_1:1;
thus fab . j = ((f . (a * b)) | (J . i)) . j by A56, A57, FUNCT_1:49
.= aij * bij by A51, A61
.= faj * fbj by A56, A57, A59, A60, FUNCT_1:49
.= (fa * fb) . j by A62, A66, GROUP_7:1 ; :: thesis: verum
end;
hence f . (a * b) = (f . a) * (f . b) by A54, GROUP_19:3; :: thesis: verum
end;
then reconsider f = f as Homomorphism of (dprod F),(product (Union F)) by GROUP_6:def 6;
take f ; :: thesis: for x being Element of (dprod F)
for i being Element of I holds x . i = (f . x) | (J . i)

thus for x being Element of (dprod F)
for i being Element of I holds x . i = (f . x) | (J . i) by A51; :: thesis: verum