Metamath Proof Explorer


Theorem phlipf

Description: The inner product operation is a function. (Contributed by Mario Carneiro, 14-Aug-2015)

Ref Expression
Hypotheses ipffn.1 ⊢ V = Base W
ipffn.2 ⊢ , ˙ = ⋅ if ⁡ W
phlipf.s ⊢ S = Scalar ⁡ W
phlipf.k ⊢ K = Base S
Assertion phlipf ⊢ W ∈ PreHil → , ˙ : V × V ⟶ K

Proof

Step Hyp Ref Expression
1 ipffn.1 ⊢ V = Base W
2 ipffn.2 ⊢ , ˙ = ⋅ if ⁡ W
3 phlipf.s ⊢ S = Scalar ⁡ W
4 phlipf.k ⊢ K = Base S
5 eqid ⊢ ⋅ 𝑖 ⁡ W = ⋅ 𝑖 ⁡ W
6 3 5 1 4 ipcl ⊢ W ∈ PreHil ∧ x ∈ V ∧ y ∈ V → x ⋅ 𝑖 ⁡ W y ∈ K
7 6 3expb ⊢ W ∈ PreHil ∧ x ∈ V ∧ y ∈ V → x ⋅ 𝑖 ⁡ W y ∈ K
8 7 ralrimivva ⊢ W ∈ PreHil → ∀ x ∈ V ∀ y ∈ V x ⋅ 𝑖 ⁡ W y ∈ K
9 1 5 2 ipffval ⊢ , ˙ = x ∈ V , y ∈ V ⟼ x ⋅ 𝑖 ⁡ W y
10 9 fmpo ⊢ ∀ x ∈ V ∀ y ∈ V x ⋅ 𝑖 ⁡ W y ∈ K ↔ , ˙ : V × V ⟶ K
11 8 10 sylib ⊢ W ∈ PreHil → , ˙ : V × V ⟶ K