let S be OrderSortedSign; for o1, o2 being OperSymbol of S
for A being OSAlgebra of S st the_result_sort_of o1 <= the_result_sort_of o2 holds
Result o1,A c= Result o2,A
let o1, o2 be OperSymbol of S; for A being OSAlgebra of S st the_result_sort_of o1 <= the_result_sort_of o2 holds
Result o1,A c= Result o2,A
let A be OSAlgebra of S; ( the_result_sort_of o1 <= the_result_sort_of o2 implies Result o1,A c= Result o2,A )
reconsider M = the Sorts of A as OrderSortedSet of S by Th17;
A1: Result o2,A =
(the Sorts of A * the ResultSort of S) . o2
by MSUALG_1:def 10
.=
the Sorts of A . (the ResultSort of S . o2)
by FUNCT_2:21
.=
the Sorts of A . (the_result_sort_of o2)
by MSUALG_1:def 7
;
assume
the_result_sort_of o1 <= the_result_sort_of o2
; Result o1,A c= Result o2,A
then A2:
M . (the_result_sort_of o1) c= M . (the_result_sort_of o2)
by Def18;
Result o1,A =
(the Sorts of A * the ResultSort of S) . o1
by MSUALG_1:def 10
.=
the Sorts of A . (the ResultSort of S . o1)
by FUNCT_2:21
.=
the Sorts of A . (the_result_sort_of o1)
by MSUALG_1:def 7
;
hence
Result o1,A c= Result o2,A
by A2, A1; verum