let n be Nat; for S being RealNormSpace
for Z being Subset of S
for f being PartFunc of S,S st Z is open & f = id ([#] S) holds
( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z )
let S be RealNormSpace; for Z being Subset of S
for f being PartFunc of S,S st Z is open & f = id ([#] S) holds
( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z )
let Z be Subset of S; for f being PartFunc of S,S st Z is open & f = id ([#] S) holds
( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z )
let f be PartFunc of S,S; ( Z is open & f = id ([#] S) implies ( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z ) )
assume A1:
( Z is open & f = id ([#] S) )
; ( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z )
reconsider L = id ([#] S) as Lipschitzian LinearOperator of S,S by LOPBAN_2:3;
A2:
dom L = [#] S
;
for i being Nat st i <= n - 1 holds
diff (L,i,([#] S)) is_differentiable_on [#] S
by NDIFF12:20;
then A3:
f is_differentiable_on n, [#] S
by A1, A2, NDIFF_6:14;
diff (L,n,([#] S)) is_continuous_on [#] S
by NDIFF_1:45, NDIFF12:20;
hence
( f is_differentiable_on n,Z & diff (f,n,Z) is_continuous_on Z )
by A1, A3, Th10; verum