let S, E, F, G be RealNormSpace; for Z being Subset of S
for B being Lipschitzian BilinearOperator of E,F,G
for W being PartFunc of S,G
for w being PartFunc of S,[:E,F:]
for u being PartFunc of S,E
for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let Z be Subset of S; for B being Lipschitzian BilinearOperator of E,F,G
for W being PartFunc of S,G
for w being PartFunc of S,[:E,F:]
for u being PartFunc of S,E
for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let B be Lipschitzian BilinearOperator of E,F,G; for W being PartFunc of S,G
for w being PartFunc of S,[:E,F:]
for u being PartFunc of S,E
for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let W be PartFunc of S,G; for w being PartFunc of S,[:E,F:]
for u being PartFunc of S,E
for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let w be PartFunc of S,[:E,F:]; for u being PartFunc of S,E
for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let u be PartFunc of S,E; for v being PartFunc of S,F st u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> holds
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
let v be PartFunc of S,F; ( u is_differentiable_on Z & u `| Z is_continuous_on Z & v is_differentiable_on Z & v `| Z is_continuous_on Z & W = B * w & w = <:u,v:> implies ( W is_differentiable_on Z & W `| Z is_continuous_on Z ) )
assume that
A1:
( u is_differentiable_on Z & u `| Z is_continuous_on Z )
and
A2:
( v is_differentiable_on Z & v `| Z is_continuous_on Z )
and
A3:
( W = B * w & w = <:u,v:> )
; ( W is_differentiable_on Z & W `| Z is_continuous_on Z )
A4:
( w is_differentiable_on Z & w `| Z is_continuous_on Z )
by A1, A2, A3, Th29;
A5:
( B is_differentiable_on [#] [:E,F:] & B `| ([#] [:E,F:]) is_continuous_on [#] [:E,F:] )
by NDIFF12:14;
w .: Z c= [#] [:E,F:]
;
hence
( W is_differentiable_on Z & W `| Z is_continuous_on Z )
by A3, A4, A5, Th23; verum