Metamath Proof Explorer


Theorem homval

Description: Value of the scalar product with a Hilbert space operator. (Contributed by NM, 20-Feb-2006) (Revised by Mario Carneiro, 16-Nov-2013) (New usage is discouraged.)

Ref Expression
Assertion homval ( ( 𝐴 ∈ ℂ ∧ 𝑇 : ℋ ⟶ ℋ ∧ 𝐵 ∈ ℋ ) → ( ( 𝐴 ·op 𝑇 ) ‘ 𝐵 ) = ( 𝐴 · ( 𝑇𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 hommval ( ( 𝐴 ∈ ℂ ∧ 𝑇 : ℋ ⟶ ℋ ) → ( 𝐴 ·op 𝑇 ) = ( 𝑥 ∈ ℋ ↦ ( 𝐴 · ( 𝑇𝑥 ) ) ) )
2 1 fveq1d ( ( 𝐴 ∈ ℂ ∧ 𝑇 : ℋ ⟶ ℋ ) → ( ( 𝐴 ·op 𝑇 ) ‘ 𝐵 ) = ( ( 𝑥 ∈ ℋ ↦ ( 𝐴 · ( 𝑇𝑥 ) ) ) ‘ 𝐵 ) )
3 fveq2 ( 𝑥 = 𝐵 → ( 𝑇𝑥 ) = ( 𝑇𝐵 ) )
4 3 oveq2d ( 𝑥 = 𝐵 → ( 𝐴 · ( 𝑇𝑥 ) ) = ( 𝐴 · ( 𝑇𝐵 ) ) )
5 eqid ( 𝑥 ∈ ℋ ↦ ( 𝐴 · ( 𝑇𝑥 ) ) ) = ( 𝑥 ∈ ℋ ↦ ( 𝐴 · ( 𝑇𝑥 ) ) )
6 ovex ( 𝐴 · ( 𝑇𝐵 ) ) ∈ V
7 4 5 6 fvmpt ( 𝐵 ∈ ℋ → ( ( 𝑥 ∈ ℋ ↦ ( 𝐴 · ( 𝑇𝑥 ) ) ) ‘ 𝐵 ) = ( 𝐴 · ( 𝑇𝐵 ) ) )
8 2 7 sylan9eq ( ( ( 𝐴 ∈ ℂ ∧ 𝑇 : ℋ ⟶ ℋ ) ∧ 𝐵 ∈ ℋ ) → ( ( 𝐴 ·op 𝑇 ) ‘ 𝐵 ) = ( 𝐴 · ( 𝑇𝐵 ) ) )
9 8 3impa ( ( 𝐴 ∈ ℂ ∧ 𝑇 : ℋ ⟶ ℋ ∧ 𝐵 ∈ ℋ ) → ( ( 𝐴 ·op 𝑇 ) ‘ 𝐵 ) = ( 𝐴 · ( 𝑇𝐵 ) ) )