let i be Nat; for K being Field
for L being Element of K
for V1 being finite-dimensional VectSp of K
for B1 being FinSequence of V1 st i in dom B1 & i <> len B1 holds
Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1))
let K be Field; for L being Element of K
for V1 being finite-dimensional VectSp of K
for B1 being FinSequence of V1 st i in dom B1 & i <> len B1 holds
Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1))
let L be Element of K; for V1 being finite-dimensional VectSp of K
for B1 being FinSequence of V1 st i in dom B1 & i <> len B1 holds
Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1))
let V1 be finite-dimensional VectSp of K; for B1 being FinSequence of V1 st i in dom B1 & i <> len B1 holds
Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1))
let B1 be FinSequence of V1; ( i in dom B1 & i <> len B1 implies Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1)) )
assume that
A1:
i in dom B1
and
A2:
i <> len B1
; Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) = (L * (B1 /. i)) + (B1 /. (i + 1))
set N = len B1;
A3:
dom B1 = Seg (len B1)
by FINSEQ_1:def 3;
i <= len B1
by A1, FINSEQ_3:25;
then
i < len B1
by A2, XXREAL_0:1;
then
( 1 <= i + 1 & i + 1 <= len B1 )
by NAT_1:11, NAT_1:13;
then A4:
i + 1 in dom B1
by A3;
set ONE = 1. (K,(len B1));
A5:
len (Line ((1. (K,(len B1))),(i + 1))) = width (1. (K,(len B1)))
by CARD_1:def 7;
width (1. (K,(len B1))) = len B1
by MATRIX_0:24;
then A6:
dom (Line ((1. (K,(len B1))),(i + 1))) = dom B1
by A5, FINSEQ_3:29;
( len (L * (Line ((1. (K,(len B1))),i))) = len (Line ((1. (K,(len B1))),i)) & len (Line ((1. (K,(len B1))),i)) = width (1. (K,(len B1))) )
by CARD_1:def 7, MATRIXR1:16;
then
dom (L * (Line ((1. (K,(len B1))),i))) = dom (Line ((1. (K,(len B1))),(i + 1)))
by A5, FINSEQ_3:29;
then A7:
dom (lmlt ((L * (Line ((1. (K,(len B1))),i))),B1)) = dom B1
by A6, MATRLIN:12;
dom (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1)) = dom B1
by A6, MATRLIN:12;
then A8:
len (lmlt ((L * (Line ((1. (K,(len B1))),i))),B1)) = len (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1))
by A7, FINSEQ_3:29;
thus Sum (lmlt ((Line ((Jordan_block (L,(len B1))),i)),B1)) =
Sum (lmlt (((L * (Line ((1. (K,(len B1))),i))) + (Line ((1. (K,(len B1))),(i + 1)))),B1))
by A1, A2, A3, Th4
.=
Sum ((lmlt ((L * (Line ((1. (K,(len B1))),i))),B1)) + (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1)))
by MATRLIN2:7
.=
(Sum (lmlt ((L * (Line ((1. (K,(len B1))),i))),B1))) + (Sum (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1)))
by A8, MATRLIN2:10
.=
(L * (Sum (lmlt ((Line ((1. (K,(len B1))),i)),B1)))) + (Sum (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1)))
by MATRLIN2:13
.=
(L * (B1 /. i)) + (Sum (lmlt ((Line ((1. (K,(len B1))),(i + 1))),B1)))
by A1, MATRLIN2:16
.=
(L * (B1 /. i)) + (B1 /. (i + 1))
by A4, MATRLIN2:16
; verum