let X be Complex_Banach_Algebra; for w, z being Element of X
for k being Nat holds (z ExpSeq) . k = (Expan_e (k,z,w)) . k
let w, z be Element of X; for k being Nat holds (z ExpSeq) . k = (Expan_e (k,z,w)) . k
let k be Nat; (z ExpSeq) . k = (Expan_e (k,z,w)) . k
0 = k - k
;
then A1:
k -' k = 0
by XREAL_1:233;
hence (Expan_e (k,z,w)) . k =
(((Coef_e k) . k) * (z #N k)) * (w #N 0)
by Def3
.=
(((Coef_e k) . k) * (z #N k)) * (1. X)
by CLOPBAN3:39
.=
((Coef_e k) . k) * (z #N k)
by VECTSP_1:def 4
.=
(1r / ((k !) * 1r)) * (z #N k)
by A1, COMPLEX1:def 4, SIN_COS:1, SIN_COS:def 7
.=
(z ExpSeq) . k
by Def1, COMPLEX1:def 4
;
verum