Metamath Proof Explorer


Theorem kbfval

Description: The outer product of two vectors, expressed as | A >. <. B | in Dirac notation. See df-kb . (Contributed by NM, 15-May-2006) (Revised by Mario Carneiro, 23-Aug-2014) (New usage is discouraged.)

Ref Expression
Assertion kbfval A B A ketbra B = x x ih B A

Proof

Step Hyp Ref Expression
1 oveq2 y = A x ih z y = x ih z A
2 1 mpteq2dv y = A x x ih z y = x x ih z A
3 oveq2 z = B x ih z = x ih B
4 3 oveq1d z = B x ih z A = x ih B A
5 4 mpteq2dv z = B x x ih z A = x x ih B A
6 df-kb ketbra = y , z x x ih z y
7 ax-hilex V
8 7 mptex x x ih B A V
9 2 5 6 8 ovmpo A B A ketbra B = x x ih B A