defpred S1[ Nat] means for S, E, F being RealNormSpace
for u being PartFunc of S,E
for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on $1 + 1,Z & v is_differentiable_on $1 + 1,Z holds
( w is_differentiable_on $1 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (($1 + 1),S,E)),(diff_SP (($1 + 1),S,F)):],(diff_SP (($1 + 1),S,[:E,F:])) st diff (w,($1 + 1),Z) = T * <:(diff (u,($1 + 1),Z)),(diff (v,($1 + 1),Z)):> );
A1: S1[ 0 ]
proof
let S, E, F be RealNormSpace; :: thesis: for u being PartFunc of S,E
for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z holds
( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> )

let u be PartFunc of S,E; :: thesis: for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z holds
( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> )

let v be PartFunc of S,F; :: thesis: for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z holds
( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> )

let w be PartFunc of S,[:E,F:]; :: thesis: for Z being Subset of S st w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z holds
( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> )

let Z be Subset of S; :: thesis: ( w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z implies ( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> ) )
assume A2: ( w = <:u,v:> & u is_differentiable_on 0 + 1,Z & v is_differentiable_on 0 + 1,Z ) ; :: thesis: ( w is_differentiable_on 0 + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> )
then ( Z c= dom u & u | Z is_differentiable_on Z & Z c= dom v & v | Z is_differentiable_on Z ) by NDIFF_6:15;
then A3: ( u is_differentiable_on Z & v is_differentiable_on Z ) ;
then A4: ( diff (w,0,Z) is_differentiable_on Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (1,S,E)),(diff_SP (1,S,F)):],(diff_SP (1,S,[:E,F:])) st
( T = CTP (S,(diff_SP (0,S,E)),(diff_SP (0,S,F))) & diff (w,1,Z) = T * <:(diff (u,1,Z)),(diff (v,1,Z)):> ) ) by A2, Th58;
A5: diff (w,0,Z) = w | Z by NDIFF_6:11;
A6: diff_SP (0,S,[:E,F:]) = [:E,F:] by NDIFF_6:7;
then w is_differentiable_on Z by A4, A5, Th3;
hence w is_differentiable_on 0 + 1,Z by A2, A3, A5, A6, Th58, NDIFF_6:15; :: thesis: ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):>
thus ex T being Lipschitzian LinearOperator of [:(diff_SP ((0 + 1),S,E)),(diff_SP ((0 + 1),S,F)):],(diff_SP ((0 + 1),S,[:E,F:])) st diff (w,(0 + 1),Z) = T * <:(diff (u,(0 + 1),Z)),(diff (v,(0 + 1),Z)):> by A4; :: thesis: verum
end;
A7: for i being Nat st S1[i] holds
S1[i + 1]
proof
let i be Nat; :: thesis: ( S1[i] implies S1[i + 1] )
assume A8: S1[i] ; :: thesis: S1[i + 1]
let S, E, F be RealNormSpace; :: thesis: for u being PartFunc of S,E
for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z holds
( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> )

let u be PartFunc of S,E; :: thesis: for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z holds
( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> )

let v be PartFunc of S,F; :: thesis: for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z holds
( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> )

let w be PartFunc of S,[:E,F:]; :: thesis: for Z being Subset of S st w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z holds
( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> )

let Z be Subset of S; :: thesis: ( w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z implies ( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> ) )
assume A9: ( w = <:u,v:> & u is_differentiable_on (i + 1) + 1,Z & v is_differentiable_on (i + 1) + 1,Z ) ; :: thesis: ( w is_differentiable_on (i + 1) + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> )
(i + 1) + 0 <= (i + 1) + 1 by XREAL_1:7;
then A10: ( u is_differentiable_on i + 1,Z & v is_differentiable_on i + 1,Z ) by A9, NDIFF_6:17;
then A11: ( w is_differentiable_on i + 1,Z & ex T0 being Lipschitzian LinearOperator of [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):],(diff_SP ((i + 1),S,[:E,F:])) st diff (w,(i + 1),Z) = T0 * <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> ) by A8, A9;
consider T0 being Lipschitzian LinearOperator of [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):],(diff_SP ((i + 1),S,[:E,F:])) such that
A12: diff (w,(i + 1),Z) = T0 * <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> by A8, A9, A10;
A13: ( diff (u,i,Z) is_differentiable_on Z & diff (v,i,Z) is_differentiable_on Z ) by A10, NDIFF_6:14;
set E1 = diff_SP ((i + 1),S,E);
set F1 = diff_SP ((i + 1),S,F);
set u1 = diff (u,(i + 1),Z);
set v1 = diff (v,(i + 1),Z);
set w1 = <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):>;
diff (u,(i + 1),Z) = (diff (u,i,Z)) `| Z by NDIFF_6:13;
then A14: dom (diff (u,(i + 1),Z)) = Z by A13, NDIFF_1:def 9;
diff (v,(i + 1),Z) = (diff (v,i,Z)) `| Z by NDIFF_6:13;
then A15: dom (diff (v,(i + 1),Z)) = Z by A13, NDIFF_1:def 9;
A16: dom <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> = (dom (diff (u,(i + 1),Z))) /\ (dom (diff (v,(i + 1),Z))) by FUNCT_3:def 7
.= Z by A14, A15 ;
A17: [:(rng (diff (u,(i + 1),Z))),(rng (diff (v,(i + 1),Z))):] c= [#] [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):] by ZFMISC_1:96;
rng <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> c= [:(rng (diff (u,(i + 1),Z))),(rng (diff (v,(i + 1),Z))):] by FUNCT_3:51;
then rng <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> c= [#] [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):] by A17, XBOOLE_1:1;
then reconsider w1 = <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> as PartFunc of S,[:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):] by A16, RELSET_1:4;
A18: diff (u,(i + 1),Z) is_differentiable_on Z by A9, NDIFF_6:14;
A19: diff (v,(i + 1),Z) is_differentiable_on Z by A9, NDIFF_6:14;
consider T1 being Lipschitzian LinearOperator of [:(diff_SP (1,S,(diff_SP ((i + 1),S,E)))),(diff_SP (1,S,(diff_SP ((i + 1),S,F)))):],(diff_SP (1,S,[:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):])) such that
A20: ( T1 = CTP (S,(diff_SP (0,S,(diff_SP ((i + 1),S,E)))),(diff_SP (0,S,(diff_SP ((i + 1),S,F))))) & diff (w1,1,Z) = T1 * <:(diff ((diff (u,(i + 1),Z)),1,Z)),(diff ((diff (v,(i + 1),Z)),1,Z)):> ) by A18, A19, Th58;
A21: diff ((diff (u,(i + 1),Z)),1,Z) = ((diff (u,(i + 1),Z)) | Z) `| Z by NDIFF_6:11
.= (diff (u,(i + 1),Z)) `| Z by A9, Th4, NDIFF_6:14
.= diff (u,((i + 1) + 1),Z) by NDIFF_6:13 ;
A22: diff ((diff (v,(i + 1),Z)),1,Z) = ((diff (v,(i + 1),Z)) | Z) `| Z by NDIFF_6:11
.= (diff (v,(i + 1),Z)) `| Z by NDIFF_6:14, A9, Th4
.= diff (v,((i + 1) + 1),Z) by NDIFF_6:13 ;
A23: diff_SP (0,S,[:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):]) = [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):] by NDIFF_6:7;
A24: diff (w1,0,Z) = w1 | Z by NDIFF_6:11;
then A25: w1 | Z is_differentiable_on Z by A18, A19, A23, Th58;
w1 is_differentiable_on Z by Th3, A25;
then A26: w1 is_differentiable_on 1,Z by A18, A19, A23, A24, Th58, NDIFF_6:15;
( T0 * w1 is_differentiable_on 1,Z & diff ((T0 * w1),1,Z) = (LTRN (1,T0,S)) * (diff (w1,1,Z)) ) by A26, Th25;
then A27: ( Z c= dom (diff (w,(i + 1),Z)) & (diff (w,(i + 1),Z)) | Z is_differentiable_on Z ) by A12, NDIFF_6:15;
then A28: diff (w,(i + 1),Z) is_differentiable_on Z ;
for k being Nat st k <= ((i + 1) + 1) - 1 holds
diff (w,k,Z) is_differentiable_on Z
proof
let k be Nat; :: thesis: ( k <= ((i + 1) + 1) - 1 implies diff (w,k,Z) is_differentiable_on Z )
assume A29: k <= ((i + 1) + 1) - 1 ; :: thesis: diff (w,k,Z) is_differentiable_on Z
end;
hence w is_differentiable_on (i + 1) + 1,Z by A11, NDIFF_6:14; :: thesis: ex T being Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) st diff (w,((i + 1) + 1),Z) = T * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):>
set L3 = LTRN (1,T0,S);
A30: (diff_SP (S,(diff_SP ((i + 1),S,E)))) . 1 = R_NormSpace_of_BoundedLinearOperators (S,(diff_SP ((i + 1),S,E))) by NDIFF_6:7
.= diff_SP (((i + 1) + 1),S,E) by NDIFF_6:10 ;
A31: (diff_SP (S,(diff_SP ((i + 1),S,F)))) . 1 = R_NormSpace_of_BoundedLinearOperators (S,(diff_SP ((i + 1),S,F))) by NDIFF_6:7
.= diff_SP (((i + 1) + 1),S,F) by NDIFF_6:10 ;
A32: diff_SP (1,S,(diff_SP ((i + 1),S,[:E,F:]))) = R_NormSpace_of_BoundedLinearOperators (S,(diff_SP ((i + 1),S,[:E,F:]))) by NDIFF_6:7
.= diff_SP (((i + 1) + 1),S,[:E,F:]) by NDIFF_6:10 ;
reconsider T3 = (LTRN (1,T0,S)) * T1 as Lipschitzian LinearOperator of [:(diff_SP (((i + 1) + 1),S,E)),(diff_SP (((i + 1) + 1),S,F)):],(diff_SP (((i + 1) + 1),S,[:E,F:])) by A30, A31, A32, LOPBAN_2:2;
take T3 ; :: thesis: diff (w,((i + 1) + 1),Z) = T3 * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):>
thus diff (w,((i + 1) + 1),Z) = (diff (w,(i + 1),Z)) `| Z by NDIFF_6:13
.= ((diff (w,(i + 1),Z)) | Z) `| Z by A28, Th4
.= diff ((diff (w,(i + 1),Z)),1,Z) by NDIFF_6:11
.= (LTRN (1,T0,S)) * (diff (w1,1,Z)) by A12, A26, Th25
.= T3 * <:(diff (u,((i + 1) + 1),Z)),(diff (v,((i + 1) + 1),Z)):> by A20, A21, A22, RELAT_1:36 ; :: thesis: verum
end;
for i being Nat holds S1[i] from NAT_1:sch 2(A1, A7);
hence for i being Nat
for S, E, F being RealNormSpace
for u being PartFunc of S,E
for v being PartFunc of S,F
for w being PartFunc of S,[:E,F:]
for Z being Subset of S st w = <:u,v:> & u is_differentiable_on i + 1,Z & v is_differentiable_on i + 1,Z holds
( w is_differentiable_on i + 1,Z & ex T being Lipschitzian LinearOperator of [:(diff_SP ((i + 1),S,E)),(diff_SP ((i + 1),S,F)):],(diff_SP ((i + 1),S,[:E,F:])) st diff (w,(i + 1),Z) = T * <:(diff (u,(i + 1),Z)),(diff (v,(i + 1),Z)):> ) ; :: thesis: verum