let X, Z be non empty set ; :: thesis: for F being Functional_Sequence of X,REAL st Z common_on_dom F holds
for a, r being positive real number st r < 1 & ( for n being natural number holds (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n) ) holds
for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) )
let F be Functional_Sequence of X,REAL ; :: thesis: ( Z common_on_dom F implies for a, r being positive real number st r < 1 & ( for n being natural number holds (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n) ) holds
for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) ) )
assume A1:
Z common_on_dom F
; :: thesis: for a, r being positive real number st r < 1 & ( for n being natural number holds (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n) ) holds
for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) )
let a, r be positive real number ; :: thesis: ( r < 1 & ( for n being natural number holds (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n) ) implies for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) ) )
assume A2:
r < 1
; :: thesis: ( ex n being natural number st not (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n) or for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) ) )
assume A3:
for n being natural number holds (F . n) - (F . (n + 1)),Z is_absolutely_bounded_by a * (r to_power n)
; :: thesis: for z being Element of Z holds
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) )
let z be Element of Z; :: thesis: ( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) )
F is_unif_conv_on Z
by A1, A2, A3, Th11;
then
F is_point_conv_on Z
by SEQFUNC:23;
then
( z in Z & Z c= dom (F . 0 ) & dom (lim F,Z) = Z )
by A1, SEQFUNC:def 10, SEQFUNC:def 14;
then
z in (dom (lim F,Z)) /\ (dom (F . 0 ))
by XBOOLE_0:def 4;
then A4:
( z in dom ((lim F,Z) - (F . 0 )) & r to_power 0 = 1 )
by POWER:29, VALUED_1:12;
then
( (lim F,Z) - (F . 0 ),Z is_absolutely_bounded_by (a * 1) / (1 - r) & z in Z /\ (dom ((lim F,Z) - (F . 0 ))) )
by A1, A2, A3, Th11, XBOOLE_0:def 4;
then
|.(((lim F,Z) - (F . 0 )) . z).| <= (a * 1) / (1 - r)
by Def1;
then
|.(((lim F,Z) . z) - ((F . 0 ) . z)).| <= (a * 1) / (1 - r)
by A4, VALUED_1:13;
hence
( (lim F,Z) . z >= ((F . 0 ) . z) - (a / (1 - r)) & (lim F,Z) . z <= ((F . 0 ) . z) + (a / (1 - r)) )
by Th1; :: thesis: verum