let K be Field; for a, L being Element of K
for J being FinSequence_of_Jordan_block of L,K holds J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) is FinSequence_of_Jordan_block of L + a,K
let a, L be Element of K; for J being FinSequence_of_Jordan_block of L,K holds J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) is FinSequence_of_Jordan_block of L + a,K
let J be FinSequence_of_Jordan_block of L,K; J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) is FinSequence_of_Jordan_block of L + a,K
set M = mlt (((len J) |-> a),(1. (K,(Len J))));
A1:
for i being Nat st i in dom (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) holds
ex n being Nat st (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block ((L + a),n)
proof
A2:
dom (mlt (((len J) |-> a),(1. (K,(Len J))))) = dom (1. (K,(Len J)))
by MATRIXJ1:def 9;
A3:
dom J = Seg (len J)
by FINSEQ_1:def 3;
A4:
dom (1. (K,(Len J))) = dom (Len J)
by MATRIXJ1:def 8;
let i be
Nat;
( i in dom (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) implies ex n being Nat st (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block ((L + a),n) )
assume A5:
i in dom (J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))))
;
ex n being Nat st (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block ((L + a),n)
A6:
i in dom J
by A5, MATRIXJ1:def 10;
then consider n being
Nat such that A7:
J . i = Jordan_block (
L,
n)
by Def3;
take
n
;
(J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block ((L + a),n)
A8:
len (J . i) = n
by A7, MATRIX_0:24;
A9:
dom (Len J) = dom J
by MATRIXJ1:def 3;
then A10:
(Len J) . i = len (J . i)
by A6, MATRIXJ1:def 3;
len ((len J) |-> a) = len J
by CARD_1:def 7;
then
dom ((len J) |-> a) = dom J
by FINSEQ_3:29;
then ((len J) |-> a) /. i =
((len J) |-> a) . i
by A6, PARTFUN1:def 6
.=
a
by A6, A3, FINSEQ_2:57
;
then (mlt (((len J) |-> a),(1. (K,(Len J))))) . i =
a * ((1. (K,(Len J))) . i)
by A6, A2, A4, A9, MATRIXJ1:def 9
.=
a * (1. (K,n))
by A6, A4, A9, A10, A8, MATRIXJ1:def 8
;
hence (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i =
(Jordan_block (L,n)) + (a * (1. (K,n)))
by A5, A7, MATRIXJ1:def 10
.=
Jordan_block (
(L + a),
n)
by Th9
;
verum
end;
J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) is Jordan-block-yielding
proof
let i be
Nat;
MATRIXJ2:def 2 ( i in dom (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) implies ex L being Element of K ex n being Nat st (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block (L,n) )
assume
i in dom (J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))))
;
ex L being Element of K ex n being Nat st (J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block (L,n)
then
ex
n being
Nat st
(J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block (
(L + a),
n)
by A1;
hence
ex
L being
Element of
K ex
n being
Nat st
(J (+) (mlt (((len J) |-> a),(1. (K,(Len J)))))) . i = Jordan_block (
L,
n)
;
verum
end;
then reconsider JM = J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) as FinSequence_of_Jordan_block of K ;
JM is FinSequence_of_Jordan_block of L + a,K
hence
J (+) (mlt (((len J) |-> a),(1. (K,(Len J))))) is FinSequence_of_Jordan_block of L + a,K
; verum