Metamath Proof Explorer


Theorem cnnvs

Description: The scalar product operation of the normed complex vector space of complex numbers. (Contributed by NM, 12-Jan-2008) (New usage is discouraged.)

Ref Expression
Hypothesis cnnvs.6 ⊢ U = + × abs
Assertion cnnvs ⊢ × = ⋅ 𝑠OLD ⁡ U

Proof

Step Hyp Ref Expression
1 cnnvs.6 ⊢ U = + × abs
2 eqid ⊢ ⋅ 𝑠OLD ⁡ U = ⋅ 𝑠OLD ⁡ U
3 2 smfval ⊢ ⋅ 𝑠OLD ⁡ U = 2 nd ⁡ 1 st ⁡ U
4 1 fveq2i ⊢ 1 st ⁡ U = 1 st ⁡ + × abs
5 opex ⊢ + × ∈ V
6 absf ⊢ abs : ℂ ⟶ ℝ
7 cnex ⊢ ℂ ∈ V
8 fex ⊢ abs : ℂ ⟶ ℝ ∧ ℂ ∈ V → abs ∈ V
9 6 7 8 mp2an ⊢ abs ∈ V
10 5 9 op1st ⊢ 1 st ⁡ + × abs = + ×
11 4 10 eqtri ⊢ 1 st ⁡ U = + ×
12 11 fveq2i ⊢ 2 nd ⁡ 1 st ⁡ U = 2 nd ⁡ + ×
13 addex ⊢ + ∈ V
14 mulex ⊢ × ∈ V
15 13 14 op2nd ⊢ 2 nd ⁡ + × = ×
16 3 12 15 3eqtrri ⊢ × = ⋅ 𝑠OLD ⁡ U