let IT1, IT2 be TermOrder of n; :: thesis: ( ( for a, b being bag of holds
( [a,b] in IT1 iff ( TotDegree a < TotDegree b or ( TotDegree a = TotDegree b & [a,b] in o ) ) ) ) & ( for a, b being bag of holds
( [a,b] in IT2 iff ( TotDegree a < TotDegree b or ( TotDegree a = TotDegree b & [a,b] in o ) ) ) ) implies IT1 = IT2 )
assume that
A36:
for a, b being bag of holds
( [a,b] in IT1 iff ( TotDegree a < TotDegree b or ( TotDegree a = TotDegree b & [a,b] in o ) ) )
and
A37:
for a, b being bag of holds
( [a,b] in IT2 iff ( TotDegree a < TotDegree b or ( TotDegree a = TotDegree b & [a,b] in o ) ) )
; :: thesis: IT1 = IT2
now let a,
b be
set ;
:: thesis: ( ( [a,b] in IT1 implies [a,b] in IT2 ) & ( [a,b] in IT2 implies [a,b] in IT1 ) )assume A40:
[a,b] in IT2
;
:: thesis: [a,b] in IT1then A41:
a in dom IT2
by RELAT_1:def 4;
b in rng IT2
by A40, RELAT_1:def 5;
then reconsider a' =
a,
b' =
b as
bag of
by A41, PRE_POLY:def 12;
(
TotDegree a' < TotDegree b' or (
TotDegree a' = TotDegree b' &
[a',b'] in o ) )
by A37, A40;
hence
[a,b] in IT1
by A36;
:: thesis: verum end;
hence
IT1 = IT2
by RELAT_1:def 2; :: thesis: verum