let n be Nat; for K being Field
for V1 being VectSp of K
for f being linear-transformation of V1,V1
for L being Scalar of K st n >= 1 holds
ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) )
let K be Field; for V1 being VectSp of K
for f being linear-transformation of V1,V1
for L being Scalar of K st n >= 1 holds
ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) )
let V1 be VectSp of K; for f being linear-transformation of V1,V1
for L being Scalar of K st n >= 1 holds
ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) )
let f be linear-transformation of V1,V1; for L being Scalar of K st n >= 1 holds
ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) )
let L be Scalar of K; ( n >= 1 implies ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) ) )
set g = L * (id V1);
defpred S1[ Nat] means ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ $1 = (f * h) + ((L * (id V1)) |^ $1) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) );
A1:
for n being Nat st 1 <= n & S1[n] holds
S1[n + 1]
proof
let n be
Nat;
( 1 <= n & S1[n] implies S1[n + 1] )
assume
1
<= n
;
( not S1[n] or S1[n + 1] )
assume
S1[
n]
;
S1[n + 1]
then consider h being
linear-transformation of
V1,
V1 such that A2:
(f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n)
and A3:
for
i being
Nat holds
(f |^ i) * h = h * (f |^ i)
;
take H =
((f * h) + ((L * (id V1)) |^ n)) + (L * h);
( (f + (L * (id V1))) |^ (n + 1) = (f * H) + ((L * (id V1)) |^ (n + 1)) & ( for i being Nat holds (f |^ i) * H = H * (f |^ i) ) )
A4:
rng (f * h) c= [#] V1
by RELAT_1:def 19;
thus (f + (L * (id V1))) |^ (n + 1) =
((f + (L * (id V1))) |^ 1) * ((f + (L * (id V1))) |^ n)
by Th20
.=
(f + (L * (id V1))) * ((f * h) + ((L * (id V1)) |^ n))
by A2, Th19
.=
(f * ((f * h) + ((L * (id V1)) |^ n))) + ((L * (id V1)) * ((f * h) + ((L * (id V1)) |^ n)))
by Lm6
.=
(f * ((f * h) + ((L * (id V1)) |^ n))) + (((L * (id V1)) * (f * h)) + ((L * (id V1)) * ((L * (id V1)) |^ n)))
by Lm7
.=
((f * ((f * h) + ((L * (id V1)) |^ n))) + ((L * (id V1)) * (f * h))) + ((L * (id V1)) * ((L * (id V1)) |^ n))
by Lm8
.=
((f * ((f * h) + ((L * (id V1)) |^ n))) + (L * ((id V1) * (f * h)))) + ((L * (id V1)) * ((L * (id V1)) |^ n))
by Lm4
.=
((f * ((f * h) + ((L * (id V1)) |^ n))) + (L * (f * h))) + ((L * (id V1)) * ((L * (id V1)) |^ n))
by A4, RELAT_1:53
.=
((f * ((f * h) + ((L * (id V1)) |^ n))) + (f * (L * h))) + ((L * (id V1)) * ((L * (id V1)) |^ n))
by Lm5
.=
(f * H) + ((L * (id V1)) * ((L * (id V1)) |^ n))
by Lm7
.=
(f * H) + (((L * (id V1)) |^ 1) * ((L * (id V1)) |^ n))
by Th19
.=
(f * H) + ((L * (id V1)) |^ (n + 1))
by Th20
;
for i being Nat holds (f |^ i) * H = H * (f |^ i)
let i be
Nat;
(f |^ i) * H = H * (f |^ i)
A5:
(f |^ i) * (f * h) =
((f |^ i) * f) * h
by RELAT_1:36
.=
((f |^ i) * (f |^ 1)) * h
by Th19
.=
(f |^ (i + 1)) * h
by Th20
.=
h * (f |^ (i + 1))
by A3
.=
h * ((f |^ 1) * (f |^ i))
by Th20
.=
(h * (f |^ 1)) * (f |^ i)
by RELAT_1:36
.=
((f |^ 1) * h) * (f |^ i)
by A3
.=
(f * h) * (f |^ i)
by Th19
;
A6:
(f |^ i) * ((L * (id V1)) |^ n) =
(f |^ i) * (((power K) . (L,n)) * (id V1))
by Lm9
.=
((power K) . (L,n)) * ((f |^ i) * (id V1))
by Lm5
.=
((power K) . (L,n)) * ((f |^ i) * (f |^ 0))
by Th18
.=
((power K) . (L,n)) * (f |^ (i + 0))
by Th20
.=
((power K) . (L,n)) * ((f |^ 0) * (f |^ i))
by Th20
.=
((power K) . (L,n)) * ((id V1) * (f |^ i))
by Th18
.=
(((power K) . (L,n)) * (id V1)) * (f |^ i)
by Lm4
.=
((L * (id V1)) |^ n) * (f |^ i)
by Lm9
;
(f |^ i) * (L * h) =
L * ((f |^ i) * h)
by Lm5
.=
L * (h * (f |^ i))
by A3
.=
(L * h) * (f |^ i)
by Lm4
;
hence (f |^ i) * H =
((f |^ i) * ((f * h) + ((L * (id V1)) |^ n))) + ((L * h) * (f |^ i))
by Lm7
.=
(((f * h) * (f |^ i)) + (((L * (id V1)) |^ n) * (f |^ i))) + ((L * h) * (f |^ i))
by A5, A6, Lm7
.=
(((f * h) + ((L * (id V1)) |^ n)) * (f |^ i)) + ((L * h) * (f |^ i))
by Lm6
.=
H * (f |^ i)
by Lm6
;
verum
end;
A7:
S1[1]
for n being Nat st 1 <= n holds
S1[n]
from NAT_1:sch 8(A7, A1);
hence
( n >= 1 implies ex h being linear-transformation of V1,V1 st
( (f + (L * (id V1))) |^ n = (f * h) + ((L * (id V1)) |^ n) & ( for i being Nat holds (f |^ i) * h = h * (f |^ i) ) ) )
; verum