let D be non empty set ; for H being Functional_Sequence of D,REAL
for X being set st H is_point_conv_on X holds
( abs H is_point_conv_on X & lim ((abs H),X) = abs (lim (H,X)) & - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) )
let H be Functional_Sequence of D,REAL; for X being set st H is_point_conv_on X holds
( abs H is_point_conv_on X & lim ((abs H),X) = abs (lim (H,X)) & - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) )
let X be set ; ( H is_point_conv_on X implies ( abs H is_point_conv_on X & lim ((abs H),X) = abs (lim (H,X)) & - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) ) )
assume A1:
H is_point_conv_on X
; ( abs H is_point_conv_on X & lim ((abs H),X) = abs (lim (H,X)) & - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) )
A3:
now let x be
Element of
D;
( x in dom (- (lim (H,X))) implies (- (lim (H,X))) . x = lim ((- H) # x) )assume
x in dom (- (lim (H,X)))
;
(- (lim (H,X))) . x = lim ((- H) # x)then A4:
x in dom (lim (H,X))
by VALUED_1:8;
then
x in X
by A1, Def14;
then A5:
H # x is
convergent
by A1, Th21;
thus (- (lim (H,X))) . x =
- ((lim (H,X)) . x)
by VALUED_1:8
.=
- (lim (H # x))
by A1, A4, Def14
.=
lim (- (H # x))
by A5, SEQ_2:10
.=
lim ((- H) # x)
by Th33
;
verum end;
A6:
X common_on_dom H
by A1, Th21;
then
X common_on_dom abs H
by Th39;
hence A7:
abs H is_point_conv_on X
by A2, Th21; ( lim ((abs H),X) = abs (lim (H,X)) & - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) )
A8:
now let x be
Element of
D;
( x in dom (abs (lim (H,X))) implies (abs (lim (H,X))) . x = lim ((abs H) # x) )assume
x in dom (abs (lim (H,X)))
;
(abs (lim (H,X))) . x = lim ((abs H) # x)then A9:
x in dom (lim (H,X))
by VALUED_1:def 11;
then
x in X
by A1, Def14;
then A10:
H # x is
convergent
by A1, Th21;
thus (abs (lim (H,X))) . x =
abs ((lim (H,X)) . x)
by VALUED_1:18
.=
abs (lim (H # x))
by A1, A9, Def14
.=
lim (abs (H # x))
by A10, SEQ_4:14
.=
lim ((abs H) # x)
by Th33
;
verum end;
dom (abs (lim (H,X))) =
dom (lim (H,X))
by VALUED_1:def 11
.=
X
by A1, Def14
;
hence
lim ((abs H),X) = abs (lim (H,X))
by A7, A8, Def14; ( - H is_point_conv_on X & lim ((- H),X) = - (lim (H,X)) )
X common_on_dom - H
by A6, Th39;
hence A12:
- H is_point_conv_on X
by A11, Th21; lim ((- H),X) = - (lim (H,X))
dom (- (lim (H,X))) =
dom (lim (H,X))
by VALUED_1:8
.=
X
by A1, Def14
;
hence
lim ((- H),X) = - (lim (H,X))
by A12, A3, Def14; verum