Metamath Proof Explorer


Theorem nvs

Description: Proportionality property of the norm of a scalar product in a normed complex vector space. (Contributed by NM, 11-Nov-2006) (New usage is discouraged.)

Ref Expression
Hypotheses nvs.1 𝑋 = ( BaseSet ‘ 𝑈 )
nvs.4 𝑆 = ( ·𝑠OLD𝑈 )
nvs.6 𝑁 = ( normCV𝑈 )
Assertion nvs ( ( 𝑈 ∈ NrmCVec ∧ 𝐴 ∈ ℂ ∧ 𝐵𝑋 ) → ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 nvs.1 𝑋 = ( BaseSet ‘ 𝑈 )
2 nvs.4 𝑆 = ( ·𝑠OLD𝑈 )
3 nvs.6 𝑁 = ( normCV𝑈 )
4 eqid ( +𝑣𝑈 ) = ( +𝑣𝑈 )
5 eqid ( 0vec𝑈 ) = ( 0vec𝑈 )
6 1 4 2 5 3 nvi ( 𝑈 ∈ NrmCVec → ( ⟨ ( +𝑣𝑈 ) , 𝑆 ⟩ ∈ CVecOLD𝑁 : 𝑋 ⟶ ℝ ∧ ∀ 𝑥𝑋 ( ( ( 𝑁𝑥 ) = 0 → 𝑥 = ( 0vec𝑈 ) ) ∧ ∀ 𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) ∧ ∀ 𝑦𝑋 ( 𝑁 ‘ ( 𝑥 ( +𝑣𝑈 ) 𝑦 ) ) ≤ ( ( 𝑁𝑥 ) + ( 𝑁𝑦 ) ) ) ) )
7 6 simp3d ( 𝑈 ∈ NrmCVec → ∀ 𝑥𝑋 ( ( ( 𝑁𝑥 ) = 0 → 𝑥 = ( 0vec𝑈 ) ) ∧ ∀ 𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) ∧ ∀ 𝑦𝑋 ( 𝑁 ‘ ( 𝑥 ( +𝑣𝑈 ) 𝑦 ) ) ≤ ( ( 𝑁𝑥 ) + ( 𝑁𝑦 ) ) ) )
8 simp2 ( ( ( ( 𝑁𝑥 ) = 0 → 𝑥 = ( 0vec𝑈 ) ) ∧ ∀ 𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) ∧ ∀ 𝑦𝑋 ( 𝑁 ‘ ( 𝑥 ( +𝑣𝑈 ) 𝑦 ) ) ≤ ( ( 𝑁𝑥 ) + ( 𝑁𝑦 ) ) ) → ∀ 𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) )
9 8 ralimi ( ∀ 𝑥𝑋 ( ( ( 𝑁𝑥 ) = 0 → 𝑥 = ( 0vec𝑈 ) ) ∧ ∀ 𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) ∧ ∀ 𝑦𝑋 ( 𝑁 ‘ ( 𝑥 ( +𝑣𝑈 ) 𝑦 ) ) ≤ ( ( 𝑁𝑥 ) + ( 𝑁𝑦 ) ) ) → ∀ 𝑥𝑋𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) )
10 7 9 syl ( 𝑈 ∈ NrmCVec → ∀ 𝑥𝑋𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) )
11 oveq2 ( 𝑥 = 𝐵 → ( 𝑦 𝑆 𝑥 ) = ( 𝑦 𝑆 𝐵 ) )
12 11 fveq2d ( 𝑥 = 𝐵 → ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( 𝑁 ‘ ( 𝑦 𝑆 𝐵 ) ) )
13 fveq2 ( 𝑥 = 𝐵 → ( 𝑁𝑥 ) = ( 𝑁𝐵 ) )
14 13 oveq2d ( 𝑥 = 𝐵 → ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝐵 ) ) )
15 12 14 eqeq12d ( 𝑥 = 𝐵 → ( ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) ↔ ( 𝑁 ‘ ( 𝑦 𝑆 𝐵 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝐵 ) ) ) )
16 fvoveq1 ( 𝑦 = 𝐴 → ( 𝑁 ‘ ( 𝑦 𝑆 𝐵 ) ) = ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) )
17 fveq2 ( 𝑦 = 𝐴 → ( abs ‘ 𝑦 ) = ( abs ‘ 𝐴 ) )
18 17 oveq1d ( 𝑦 = 𝐴 → ( ( abs ‘ 𝑦 ) · ( 𝑁𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) )
19 16 18 eqeq12d ( 𝑦 = 𝐴 → ( ( 𝑁 ‘ ( 𝑦 𝑆 𝐵 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝐵 ) ) ↔ ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) ) )
20 15 19 rspc2v ( ( 𝐵𝑋𝐴 ∈ ℂ ) → ( ∀ 𝑥𝑋𝑦 ∈ ℂ ( 𝑁 ‘ ( 𝑦 𝑆 𝑥 ) ) = ( ( abs ‘ 𝑦 ) · ( 𝑁𝑥 ) ) → ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) ) )
21 10 20 syl5 ( ( 𝐵𝑋𝐴 ∈ ℂ ) → ( 𝑈 ∈ NrmCVec → ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) ) )
22 21 3impia ( ( 𝐵𝑋𝐴 ∈ ℂ ∧ 𝑈 ∈ NrmCVec ) → ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) )
23 22 3com13 ( ( 𝑈 ∈ NrmCVec ∧ 𝐴 ∈ ℂ ∧ 𝐵𝑋 ) → ( 𝑁 ‘ ( 𝐴 𝑆 𝐵 ) ) = ( ( abs ‘ 𝐴 ) · ( 𝑁𝐵 ) ) )