let T be non empty TopSpace; for ADD being BinOp of (Funcs the carrier of T,REAL ) st ( for f1, f2 being RealMap of T holds ADD . f1,f2 = f1 + f2 ) holds
for map9 being Element of Funcs the carrier of T,REAL st map9 is_a_unity_wrt ADD holds
map9 is continuous
let ADD be BinOp of (Funcs the carrier of T,REAL ); ( ( for f1, f2 being RealMap of T holds ADD . f1,f2 = f1 + f2 ) implies for map9 being Element of Funcs the carrier of T,REAL st map9 is_a_unity_wrt ADD holds
map9 is continuous )
assume A1:
for f1, f2 being RealMap of T holds ADD . f1,f2 = f1 + f2
; for map9 being Element of Funcs the carrier of T,REAL st map9 is_a_unity_wrt ADD holds
map9 is continuous
set F = Funcs the carrier of T,REAL ;
let map9 be Element of Funcs the carrier of T,REAL ; ( map9 is_a_unity_wrt ADD implies map9 is continuous )
assume A2:
map9 is_a_unity_wrt ADD
; map9 is continuous
A3:
for x being Point of T holds map9 . x = 0
proof
assume
ex
x being
Point of
T st
map9 . x <> 0
;
contradiction
then consider x being
Point of
T such that A4:
map9 . x <> 0
;
ADD . map9,
map9 = map9
by A2, BINOP_1:11;
then
map9 + map9 = map9
by A1;
then
(map9 . x) + (map9 . x) = map9 . x
by Def7;
hence
contradiction
by A4;
verum
end;
reconsider map99 = map9 as Function of T,R^1 by TOPMETR:24;
for A being Subset of T holds map99 .: (Cl A) c= Cl (map99 .: A)
then
map99 is continuous
by TOPS_2:57;
hence
map9 is continuous
by TOPREAL6:83; verum