let X be Complex_Banach_Algebra; for z, w being Element of X
for k, n being Element of NAT holds abs ((Partial_Sums ||.(Conj (k,z,w)).||) . n) = (Partial_Sums ||.(Conj (k,z,w)).||) . n
let z, w be Element of X; for k, n being Element of NAT holds abs ((Partial_Sums ||.(Conj (k,z,w)).||) . n) = (Partial_Sums ||.(Conj (k,z,w)).||) . n
let k, n be Element of NAT ; abs ((Partial_Sums ||.(Conj (k,z,w)).||) . n) = (Partial_Sums ||.(Conj (k,z,w)).||) . n
A1:
0 <= n
by NAT_1:2;
then
Partial_Sums ||.(Conj (k,z,w)).|| is non-decreasing
by SERIES_1:19;
then A3:
(Partial_Sums ||.(Conj (k,z,w)).||) . 0 <= (Partial_Sums ||.(Conj (k,z,w)).||) . n
by A1, SEQM_3:12;
A4:
(Partial_Sums ||.(Conj (k,z,w)).||) . 0 = ||.(Conj (k,z,w)).|| . 0
by SERIES_1:def 1;
0 <= ||.(Conj (k,z,w)).|| . 0
by A2;
hence
abs ((Partial_Sums ||.(Conj (k,z,w)).||) . n) = (Partial_Sums ||.(Conj (k,z,w)).||) . n
by A3, A4, ABSVALUE:def 1; verum