let E, F be RealNormSpace; for Z being non empty Subset of E
for L1 being PartFunc of E,F
for L0 being Point of F st Z is open & L1 = Z --> L0 holds
for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z )
let Z be non empty Subset of E; for L1 being PartFunc of E,F
for L0 being Point of F st Z is open & L1 = Z --> L0 holds
for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z )
let L1 be PartFunc of E,F; for L0 being Point of F st Z is open & L1 = Z --> L0 holds
for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z )
let L0 be Point of F; ( Z is open & L1 = Z --> L0 implies for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z ) )
assume A1:
( Z is open & L1 = Z --> L0 )
; for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z )
defpred S1[ Nat] means ( ex P being Point of (diff_SP ($1,E,F)) st diff (L1,$1,Z) = Z --> P & diff (L1,$1,Z) is_differentiable_on Z & (diff (L1,$1,Z)) `| Z is_continuous_on Z );
A2:
S1[ 0 ]
proof
A3:
diff_SP (
0,
E,
F)
= F
by NDIFF_6:7;
A4:
diff (
L1,
0,
Z) =
L1 | Z
by NDIFF_6:11
.=
L1
by A1
;
thus
ex
P being
Point of
(diff_SP (0,E,F)) st
diff (
L1,
0,
Z)
= Z --> P
by A1, A3, A4;
( diff (L1,0,Z) is_differentiable_on Z & (diff (L1,0,Z)) `| Z is_continuous_on Z )
thus
diff (
L1,
0,
Z)
is_differentiable_on Z
by A1, A3, A4, Th48;
(diff (L1,0,Z)) `| Z is_continuous_on Z
thus
(diff (L1,0,Z)) `| Z is_continuous_on Z
by A1, A3, A4, Th48;
verum
end;
A5:
for i being Nat st S1[i] holds
S1[i + 1]
proof
let i be
Nat;
( S1[i] implies S1[i + 1] )
assume
S1[
i]
;
S1[i + 1]
then consider P being
Point of
(diff_SP (i,E,F)) such that A6:
diff (
L1,
i,
Z)
= Z --> P
;
A7:
diff_SP (
(i + 1),
E,
F)
= R_NormSpace_of_BoundedLinearOperators (
E,
(diff_SP (i,E,F)))
by NDIFF_6:10;
A8:
diff (
L1,
(i + 1),
Z) =
(diff (L1,i,Z)) `| Z
by NDIFF_6:13
.=
Z --> (0. (diff_SP ((i + 1),E,F)))
by A1, A6, A7, Th48
;
hence
ex
P being
Point of
(diff_SP ((i + 1),E,F)) st
diff (
L1,
(i + 1),
Z)
= Z --> P
;
( diff (L1,(i + 1),Z) is_differentiable_on Z & (diff (L1,(i + 1),Z)) `| Z is_continuous_on Z )
thus
diff (
L1,
(i + 1),
Z)
is_differentiable_on Z
by A1, A8, Th48;
(diff (L1,(i + 1),Z)) `| Z is_continuous_on Z
thus
(diff (L1,(i + 1),Z)) `| Z is_continuous_on Z
by A1, A8, Th48;
verum
end;
for i being Nat holds S1[i]
from NAT_1:sch 2(A2, A5);
hence
for i being Nat holds
( ex P being Point of (diff_SP (i,E,F)) st diff (L1,i,Z) = Z --> P & diff (L1,i,Z) is_differentiable_on Z & (diff (L1,i,Z)) `| Z is_continuous_on Z )
; verum