let G be non-trivial RealNormSpace-Sequence; for h being FinSequence of (product G)
for y, x being Point of (product G)
for y0, Z being Element of product (carr G)
for j being Element of NAT st y = y0 & Z = 0. (product G) & len h = (len G) + 1 & 1 <= j & j <= len G & ( for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i))) ) holds
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y
let h be FinSequence of (product G); for y, x being Point of (product G)
for y0, Z being Element of product (carr G)
for j being Element of NAT st y = y0 & Z = 0. (product G) & len h = (len G) + 1 & 1 <= j & j <= len G & ( for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i))) ) holds
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y
let y, x be Point of (product G); for y0, Z being Element of product (carr G)
for j being Element of NAT st y = y0 & Z = 0. (product G) & len h = (len G) + 1 & 1 <= j & j <= len G & ( for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i))) ) holds
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y
let y0, Z be Element of product (carr G); for j being Element of NAT st y = y0 & Z = 0. (product G) & len h = (len G) + 1 & 1 <= j & j <= len G & ( for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i))) ) holds
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y
let j be Element of NAT ; ( y = y0 & Z = 0. (product G) & len h = (len G) + 1 & 1 <= j & j <= len G & ( for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i))) ) implies ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y )
assume that
A1:
y = y0
and
A2:
Z = 0. (product G)
and
A3:
( len h = (len G) + 1 & 1 <= j & j <= len G )
and
A4:
for i being Nat st i in dom h holds
h /. i = Z +* (y0 | (Seg (((len G) + 1) -' i)))
; ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . y
x + (h /. j) = (reproj ((modetrans (G,(((len G) + 1) -' j))),(x + (h /. (j + 1))))) . ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y))
by A1, A2, A3, A4, Th54;
then
(proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. j)) = (proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)
by Th46;
then A5:
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = (proj (modetrans (G,(((len G) + 1) -' j)))) . ((x + (h /. j)) - (x + (h /. (j + 1))))
by Th37;
(x + (h /. j)) - (x + (h /. (j + 1))) =
(((h /. j) + x) - x) - (h /. (j + 1))
by RLVECT_1:27
.=
((h /. j) + (x - x)) - (h /. (j + 1))
by RLVECT_1:28
.=
((h /. j) + (0. (product G))) - (h /. (j + 1))
by RLVECT_1:15
.=
(h /. j) - (h /. (j + 1))
by RLVECT_1:4
;
then A6:
((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) = ((proj (modetrans (G,(((len G) + 1) -' j)))) . (h /. j)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (h /. (j + 1)))
by A5, Th37;
y0 is Element of the carrier of (product G)
by Th10;
then A7:
dom y0 = Seg (len G)
by FINSEQ_1:89;
j in Seg (len G)
by A3;
then
((len G) -' j) + 1 in Seg (len G)
by NAT_2:6;
then A8:
((len G) + 1) -' j in Seg (len G)
by A3, NAT_D:38;
A9:
j < (len G) + 1
by A3, NAT_1:13;
then
((len G) + 1) -' j in Seg (((len G) + 1) -' j)
by FINSEQ_1:3, NAT_D:36;
then A10:
((len G) + 1) -' j in dom (y0 | (Seg (((len G) + 1) -' j)))
by A7, A8, RELAT_1:57;
((len G) + 1) -' j = (((len G) + 1) -' (j + 1)) + 1
by A9, NAT_2:7;
then A11:
((len G) + 1) -' (j + 1) < ((len G) + 1) -' j
by NAT_1:13;
dom (y0 | (Seg (((len G) + 1) -' (j + 1)))) c= Seg (((len G) + 1) -' (j + 1))
by RELAT_1:58;
then A12:
not ((len G) + 1) -' j in dom (y0 | (Seg (((len G) + 1) -' (j + 1))))
by A11, FINSEQ_1:1;
reconsider h1 = h /. j as Element of product (carr G) by Th10;
reconsider h2 = h /. (j + 1) as Element of product (carr G) by Th10;
j in Seg (len h)
by A3, A9;
then
j in dom h
by FINSEQ_1:def 3;
then A13:
h /. j = Z +* (y0 | (Seg (((len G) + 1) -' j)))
by A4;
((len G) + 1) -' j in dom G
by A8, FINSEQ_1:def 3;
then A14:
modetrans (G,(((len G) + 1) -' j)) = ((len G) + 1) -' j
by Def5;
then A15: (proj (modetrans (G,(((len G) + 1) -' j)))) . (h /. j) =
h1 . (((len G) + 1) -' j)
by Def3
.=
(y0 | (Seg (((len G) + 1) -' j))) . (((len G) + 1) -' j)
by A10, A13, FUNCT_4:13
.=
y0 . (((len G) + 1) -' j)
by A10, FUNCT_1:47
.=
(proj (modetrans (G,(((len G) + 1) -' j)))) . y
by A1, A14, Def3
;
( 1 <= j + 1 & j + 1 <= len h )
by A3, NAT_1:12, XREAL_1:6;
then
j + 1 in Seg (len h)
;
then
j + 1 in dom h
by FINSEQ_1:def 3;
then A16:
h /. (j + 1) = Z +* (y0 | (Seg (((len G) + 1) -' (j + 1))))
by A4;
(proj (modetrans (G,(((len G) + 1) -' j)))) . (h /. (j + 1)) =
h2 . (((len G) + 1) -' j)
by A14, Def3
.=
Z . (((len G) + 1) -' j)
by A16, A12, FUNCT_4:11
.=
(proj (modetrans (G,(((len G) + 1) -' j)))) . (0. (product G))
by A14, A2, Def3
;
hence ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + y)) - ((proj (modetrans (G,(((len G) + 1) -' j)))) . (x + (h /. (j + 1)))) =
(proj (modetrans (G,(((len G) + 1) -' j)))) . (y - (0. (product G)))
by A6, A15, Th37
.=
(proj (modetrans (G,(((len G) + 1) -' j)))) . y
by RLVECT_1:13
;
verum