let o1, o2 be Function of [:(Funcs (A,D1)),(Funcs (A,D2)):],(Funcs (A,D)); ( ( for f1 being Element of Funcs (A,D1)
for f2 being Element of Funcs (A,D2) holds o1 . (f1,f2) = f .: (f1,f2) ) & ( for f1 being Element of Funcs (A,D1)
for f2 being Element of Funcs (A,D2) holds o2 . (f1,f2) = f .: (f1,f2) ) implies o1 = o2 )
assume that
A2:
for f1 being Element of Funcs (A,D1)
for f2 being Element of Funcs (A,D2) holds o1 . (f1,f2) = f .: (f1,f2)
and
A3:
for f1 being Element of Funcs (A,D1)
for f2 being Element of Funcs (A,D2) holds o2 . (f1,f2) = f .: (f1,f2)
; o1 = o2
now for f1 being Element of Funcs (A,D1)
for f2 being Element of Funcs (A,D2) holds o1 . (f1,f2) = o2 . (f1,f2)let f1 be
Element of
Funcs (
A,
D1);
for f2 being Element of Funcs (A,D2) holds o1 . (f1,f2) = o2 . (f1,f2)let f2 be
Element of
Funcs (
A,
D2);
o1 . (f1,f2) = o2 . (f1,f2)thus o1 . (
f1,
f2) =
f .: (
f1,
f2)
by A2
.=
o2 . (
f1,
f2)
by A3
;
verum end;
hence
o1 = o2
; verum