let m, n, i be Nat; for K being Field
for a being Element of K
for L being Linear_Combination of n -VectSp_over K
for M being Matrix of m,n,K st i in Seg (len M) & a = L . (M . i) holds
Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i)
let K be Field; for a being Element of K
for L being Linear_Combination of n -VectSp_over K
for M being Matrix of m,n,K st i in Seg (len M) & a = L . (M . i) holds
Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i)
let a be Element of K; for L being Linear_Combination of n -VectSp_over K
for M being Matrix of m,n,K st i in Seg (len M) & a = L . (M . i) holds
Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i)
let L be Linear_Combination of n -VectSp_over K; for M being Matrix of m,n,K st i in Seg (len M) & a = L . (M . i) holds
Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i)
let M be Matrix of m,n,K; ( i in Seg (len M) & a = L . (M . i) implies Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i) )
assume that
A1:
i in Seg (len M)
and
A2:
a = L . (M . i)
; Line (FinS2MX (L (#) (MX2FinS M))),i = a * (Line M,i)
set MX = MX2FinS M;
set LM = L (#) (MX2FinS M);
i in dom M
by A1, FINSEQ_1:def 3;
then A3:
M . i = (MX2FinS M) /. i
by PARTFUN1:def 8;
len M = m
by MATRIX_1:def 3;
then A4:
Line M,i = M . i
by A1, MATRIX_2:10;
then reconsider L = Line M,i as Element of n -tuples_on the carrier of K by A3, Th102;
set FLM = FinS2MX (L (#) (MX2FinS M));
A5:
len (L (#) (MX2FinS M)) = len M
by VECTSP_6:def 8;
then A6:
i in dom (FinS2MX (L (#) (MX2FinS M)))
by A1, FINSEQ_1:def 3;
Line (FinS2MX (L (#) (MX2FinS M))),i = (FinS2MX (L (#) (MX2FinS M))) . i
by A1, A5, MATRIX_2:10;
hence Line (FinS2MX (L (#) (MX2FinS M))),i =
a * ((MX2FinS M) /. i)
by A2, A3, A6, VECTSP_6:def 8
.=
a * L
by A3, A4, Th102
.=
a * (Line M,i)
;
verum