let A be partial non-empty UAStr ; :: thesis: for R being Equivalence_Relation of the carrier of A st R c= DomRel A holds
( R |^ A is total & R |^ A is symmetric & R |^ A is transitive )
let R be Equivalence_Relation of the carrier of A; :: thesis: ( R c= DomRel A implies ( R |^ A is total & R |^ A is symmetric & R |^ A is transitive ) )
assume A1:
R c= DomRel A
; :: thesis: ( R |^ A is total & R |^ A is symmetric & R |^ A is transitive )
then
R |^ A is_reflexive_in the carrier of A
by RELAT_2:def 1;
then A3:
( dom (R |^ A) = the carrier of A & field (R |^ A) = the carrier of A )
by ORDERS_1:98;
hence
R |^ A is total
by PARTFUN1:def 4; :: thesis: ( R |^ A is symmetric & R |^ A is transitive )
now let x,
y be
set ;
:: thesis: ( x in the carrier of A & y in the carrier of A & [x,y] in R |^ A implies [y,x] in R |^ A )assume
(
x in the
carrier of
A &
y in the
carrier of
A )
;
:: thesis: ( [x,y] in R |^ A implies [y,x] in R |^ A )then reconsider a =
x,
b =
y as
Element of
A ;
assume A4:
[x,y] in R |^ A
;
:: thesis: [y,x] in R |^ Athen A5:
(
[a,b] in R & ( for
f being
operation of
A for
p,
q being
FinSequence st
(p ^ <*a*>) ^ q in dom f &
(p ^ <*b*>) ^ q in dom f holds
[(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*b*>) ^ q))] in R ) )
by Def6;
now thus
[b,a] in R
by A5, EQREL_1:12;
:: thesis: for f being operation of A
for p, q being FinSequence st (p ^ <*b*>) ^ q in dom f & (p ^ <*a*>) ^ q in dom f holds
[(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*a*>) ^ q))] in Rlet f be
operation of
A;
:: thesis: for p, q being FinSequence st (p ^ <*b*>) ^ q in dom f & (p ^ <*a*>) ^ q in dom f holds
[(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*a*>) ^ q))] in Rlet p,
q be
FinSequence;
:: thesis: ( (p ^ <*b*>) ^ q in dom f & (p ^ <*a*>) ^ q in dom f implies [(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*a*>) ^ q))] in R )assume
(
(p ^ <*b*>) ^ q in dom f &
(p ^ <*a*>) ^ q in dom f )
;
:: thesis: [(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*a*>) ^ q))] in Rthen
[(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*b*>) ^ q))] in R
by A4, Def6;
hence
[(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*a*>) ^ q))] in R
by EQREL_1:12;
:: thesis: verum end; hence
[y,x] in R |^ A
by Def6;
:: thesis: verum end;
then
R |^ A is_symmetric_in the carrier of A
by RELAT_2:def 3;
hence
R |^ A is symmetric
by A3, RELAT_2:def 11; :: thesis: R |^ A is transitive
now let x,
y,
z be
set ;
:: thesis: ( x in the carrier of A & y in the carrier of A & z in the carrier of A & [x,y] in R |^ A & [y,z] in R |^ A implies [x,z] in R |^ A )assume
(
x in the
carrier of
A &
y in the
carrier of
A &
z in the
carrier of
A )
;
:: thesis: ( [x,y] in R |^ A & [y,z] in R |^ A implies [x,z] in R |^ A )then reconsider a =
x,
b =
y,
c =
z as
Element of
A ;
assume A6:
(
[x,y] in R |^ A &
[y,z] in R |^ A )
;
:: thesis: [x,z] in R |^ AA7:
now let f be
operation of
A;
:: thesis: for p, q being FinSequence st (p ^ <*a*>) ^ q in dom f & (p ^ <*c*>) ^ q in dom f holds
[(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*c*>) ^ q))] in Rlet p,
q be
FinSequence;
:: thesis: ( (p ^ <*a*>) ^ q in dom f & (p ^ <*c*>) ^ q in dom f implies [(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*c*>) ^ q))] in R )
[a,b] in R
by A6, Def6;
then
( (
(p ^ <*a*>) ^ q in dom f implies
(p ^ <*b*>) ^ q in dom f ) & (
(p ^ <*b*>) ^ q in dom f implies
(p ^ <*a*>) ^ q in dom f ) & (
(p ^ <*a*>) ^ q in dom f &
(p ^ <*b*>) ^ q in dom f implies
[(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*b*>) ^ q))] in R ) & (
(p ^ <*b*>) ^ q in dom f &
(p ^ <*c*>) ^ q in dom f implies
[(f . ((p ^ <*b*>) ^ q)),(f . ((p ^ <*c*>) ^ q))] in R ) )
by A1, A6, Def5, Def6;
hence
(
(p ^ <*a*>) ^ q in dom f &
(p ^ <*c*>) ^ q in dom f implies
[(f . ((p ^ <*a*>) ^ q)),(f . ((p ^ <*c*>) ^ q))] in R )
by EQREL_1:13;
:: thesis: verum end;
(
[a,b] in R &
[b,c] in R )
by A6, Def6;
then
[a,c] in R
by EQREL_1:13;
hence
[x,z] in R |^ A
by A7, Def6;
:: thesis: verum end;
then
R |^ A is_transitive_in the carrier of A
by RELAT_2:def 8;
hence
R |^ A is transitive
by A3, RELAT_2:def 16; :: thesis: verum