Metamath Proof Explorer


Theorem smfval

Description: Value of the function for the scalar multiplication operation on a normed complex vector space. (Contributed by NM, 24-Apr-2007) (New usage is discouraged.)

Ref Expression
Hypothesis smfval.4 ⊢ S = ⋅ 𝑠OLD ⁡ U
Assertion smfval ⊢ S = 2 nd ⁡ 1 st ⁡ U

Proof

Step Hyp Ref Expression
1 smfval.4 ⊢ S = ⋅ 𝑠OLD ⁡ U
2 df-sm ⊢ ⋅ 𝑠OLD = 2 nd ∘ 1 st
3 2 fveq1i ⊢ ⋅ 𝑠OLD ⁡ U = 2 nd ∘ 1 st ⁡ U
4 fo1st ⊢ 1 st : V ⟶ onto V
5 fof ⊢ 1 st : V ⟶ onto V → 1 st : V ⟶ V
6 4 5 ax-mp ⊢ 1 st : V ⟶ V
7 fvco3 ⊢ 1 st : V ⟶ V ∧ U ∈ V → 2 nd ∘ 1 st ⁡ U = 2 nd ⁡ 1 st ⁡ U
8 6 7 mpan ⊢ U ∈ V → 2 nd ∘ 1 st ⁡ U = 2 nd ⁡ 1 st ⁡ U
9 3 8 eqtrid ⊢ U ∈ V → ⋅ 𝑠OLD ⁡ U = 2 nd ⁡ 1 st ⁡ U
10 fvprc ⊢ ¬ U ∈ V → ⋅ 𝑠OLD ⁡ U = ∅
11 fvprc ⊢ ¬ U ∈ V → 1 st ⁡ U = ∅
12 11 fveq2d ⊢ ¬ U ∈ V → 2 nd ⁡ 1 st ⁡ U = 2 nd ⁡ ∅
13 2nd0 ⊢ 2 nd ⁡ ∅ = ∅
14 12 13 eqtr2di ⊢ ¬ U ∈ V → ∅ = 2 nd ⁡ 1 st ⁡ U
15 10 14 eqtrd ⊢ ¬ U ∈ V → ⋅ 𝑠OLD ⁡ U = 2 nd ⁡ 1 st ⁡ U
16 9 15 pm2.61i ⊢ ⋅ 𝑠OLD ⁡ U = 2 nd ⁡ 1 st ⁡ U
17 1 16 eqtri ⊢ S = 2 nd ⁡ 1 st ⁡ U