let K be Field; for L, a 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 L, a 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_1:25;
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 FINSEQ_1:def 18;
then
dom ((len J) |-> a) = dom J
by FINSEQ_3:31;
then ((len J) |-> a) /. i =
((len J) |-> a) . i
by A6, PARTFUN1:def 8
.=
a
by A6, A3, FINSEQ_2:71
;
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