Metamath Proof Explorer


Theorem hi02

Description: Inner product with the 0 vector. (Contributed by NM, 13-Oct-1999) (New usage is discouraged.)

Ref Expression
Assertion hi02 ( 𝐴 ∈ ℋ → ( 𝐴 ·ih 0ℎ ) = 0 )

Proof

Step Hyp Ref Expression
1 ax-hv0cl ⊢ 0ℎ ∈ ℋ
2 ax-his1 ⊢ ( ( 𝐴 ∈ ℋ ∧ 0ℎ ∈ ℋ ) → ( 𝐴 ·ih 0ℎ ) = ( ∗ ‘ ( 0ℎ ·ih 𝐴 ) ) )
3 1 2 mpan2 ⊢ ( 𝐴 ∈ ℋ → ( 𝐴 ·ih 0ℎ ) = ( ∗ ‘ ( 0ℎ ·ih 𝐴 ) ) )
4 hi01 ⊢ ( 𝐴 ∈ ℋ → ( 0ℎ ·ih 𝐴 ) = 0 )
5 4 fveq2d ⊢ ( 𝐴 ∈ ℋ → ( ∗ ‘ ( 0ℎ ·ih 𝐴 ) ) = ( ∗ ‘ 0 ) )
6 cj0 ⊢ ( ∗ ‘ 0 ) = 0
7 5 6 eqtrdi ⊢ ( 𝐴 ∈ ℋ → ( ∗ ‘ ( 0ℎ ·ih 𝐴 ) ) = 0 )
8 3 7 eqtrd ⊢ ( 𝐴 ∈ ℋ → ( 𝐴 ·ih 0ℎ ) = 0 )