let Rseq be Function of [:NAT,NAT:],REAL; for r being Real st Rseq is P-convergent holds
( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) )
let r be Real; ( Rseq is P-convergent implies ( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) ) )
assume a1:
Rseq is P-convergent
; ( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) )
now ( r <> 0 implies ( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) ) )assume
r <> 0
;
( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) )then a5:
|.r.| > 0
by COMPLEX1:47;
a7:
now for e being Real st 0 < e holds
ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < elet e be
Real;
( 0 < e implies ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < e )assume
0 < e
;
ex N being Nat st
for n, m being Nat st n >= N & m >= N holds
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < ethen consider N being
Nat such that a6:
for
n,
m being
Nat st
n >= N &
m >= N holds
|.((Rseq . (n,m)) - (P-lim Rseq)).| < e / |.r.|
by a1, a5, def6;
take N =
N;
for n, m being Nat st n >= N & m >= N holds
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < ehereby verum
let n,
m be
Nat;
( n >= N & m >= N implies |.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < e )assume
(
n >= N &
m >= N )
;
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < ethen
|.((Rseq . (n,m)) - (P-lim Rseq)).| < e / |.r.|
by a6;
then
|.r.| * |.((Rseq . (n,m)) - (P-lim Rseq)).| < (e / |.r.|) * |.r.|
by a5, XREAL_1:68;
then
|.r.| * |.((Rseq . (n,m)) - (P-lim Rseq)).| < |.r.| / (|.r.| / e)
by XCMPLX_1:79;
then
|.r.| * |.((Rseq . (n,m)) - (P-lim Rseq)).| < e
by a5, XCMPLX_1:52;
then
|.(r * ((Rseq . (n,m)) - (P-lim Rseq))).| < e
by COMPLEX1:65;
then
|.((r * (Rseq . (n,m))) - (r * (P-lim Rseq))).| < e
;
hence
|.(((r (#) Rseq) . (n,m)) - (r * (P-lim Rseq))).| < e
by VALUED_1:6;
verum
end; end; hence
r (#) Rseq is
P-convergent
;
P-lim (r (#) Rseq) = r * (P-lim Rseq)hence
P-lim (r (#) Rseq) = r * (P-lim Rseq)
by a7, def6;
verum end;
hence
( r (#) Rseq is P-convergent & P-lim (r (#) Rseq) = r * (P-lim Rseq) )
by a4; verum