Metamath Proof Explorer


Theorem kbval

Description: The value of the operator resulting from the outer product | A >. <. B | of two vectors. Equation 8.1 of Prugovecki p. 376. (Contributed by NM, 15-May-2006) (Revised by Mario Carneiro, 16-Nov-2013) (New usage is discouraged.)

Ref Expression
Assertion kbval
|- ( ( A e. ~H /\ B e. ~H /\ C e. ~H ) -> ( ( A ketbra B ) ` C ) = ( ( C .ih B ) .h A ) )

Proof

Step Hyp Ref Expression
1 kbfval
 |-  ( ( A e. ~H /\ B e. ~H ) -> ( A ketbra B ) = ( x e. ~H |-> ( ( x .ih B ) .h A ) ) )
2 1 fveq1d
 |-  ( ( A e. ~H /\ B e. ~H ) -> ( ( A ketbra B ) ` C ) = ( ( x e. ~H |-> ( ( x .ih B ) .h A ) ) ` C ) )
3 oveq1
 |-  ( x = C -> ( x .ih B ) = ( C .ih B ) )
4 3 oveq1d
 |-  ( x = C -> ( ( x .ih B ) .h A ) = ( ( C .ih B ) .h A ) )
5 eqid
 |-  ( x e. ~H |-> ( ( x .ih B ) .h A ) ) = ( x e. ~H |-> ( ( x .ih B ) .h A ) )
6 ovex
 |-  ( ( C .ih B ) .h A ) e. _V
7 4 5 6 fvmpt
 |-  ( C e. ~H -> ( ( x e. ~H |-> ( ( x .ih B ) .h A ) ) ` C ) = ( ( C .ih B ) .h A ) )
8 2 7 sylan9eq
 |-  ( ( ( A e. ~H /\ B e. ~H ) /\ C e. ~H ) -> ( ( A ketbra B ) ` C ) = ( ( C .ih B ) .h A ) )
9 8 3impa
 |-  ( ( A e. ~H /\ B e. ~H /\ C e. ~H ) -> ( ( A ketbra B ) ` C ) = ( ( C .ih B ) .h A ) )