Metamath Proof Explorer


Theorem pprodss4v

Description: The parallel product is a subclass of ( (V X. V ) X. (V X. V ) ) . (Contributed by Scott Fenton, 11-Apr-2014) (Revised by Mario Carneiro, 19-Apr-2014) (Proof shortened by Peter Mazsa, 2-Oct-2022)

Ref Expression
Assertion pprodss4v pprod ( 𝐴 , 𝐵 ) ⊆ ( ( V × V ) × ( V × V ) )

Proof

Step Hyp Ref Expression
1 df-pprod pprod ( 𝐴 , 𝐵 ) = ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) )
2 txprel Rel ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) )
3 txpss3v ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ⊆ ( V × ( V × V ) )
4 3 sseli ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → ⟨ 𝑥 , 𝑦 ⟩ ∈ ( V × ( V × V ) ) )
5 opelxp2 ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( V × ( V × V ) ) → 𝑦 ∈ ( V × V ) )
6 4 5 syl ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑦 ∈ ( V × V ) )
7 elvv ( 𝑦 ∈ ( V × V ) ↔ ∃ 𝑧𝑤 𝑦 = ⟨ 𝑧 , 𝑤 ⟩ )
8 opeq2 ( 𝑦 = ⟨ 𝑧 , 𝑤 ⟩ → ⟨ 𝑥 , 𝑦 ⟩ = ⟨ 𝑥 , ⟨ 𝑧 , 𝑤 ⟩ ⟩ )
9 8 eleq1d ( 𝑦 = ⟨ 𝑧 , 𝑤 ⟩ → ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ↔ ⟨ 𝑥 , ⟨ 𝑧 , 𝑤 ⟩ ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ) )
10 df-br ( 𝑥 ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ⟨ 𝑧 , 𝑤 ⟩ ↔ ⟨ 𝑥 , ⟨ 𝑧 , 𝑤 ⟩ ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) )
11 vex 𝑥 ∈ V
12 vex 𝑧 ∈ V
13 vex 𝑤 ∈ V
14 11 12 13 brtxp ( 𝑥 ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ⟨ 𝑧 , 𝑤 ⟩ ↔ ( 𝑥 ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) 𝑧𝑥 ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) 𝑤 ) )
15 11 12 brco ( 𝑥 ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) 𝑧 ↔ ∃ 𝑦 ( 𝑥 ( 1st ↾ ( V × V ) ) 𝑦𝑦 𝐴 𝑧 ) )
16 vex 𝑦 ∈ V
17 16 brresi ( 𝑥 ( 1st ↾ ( V × V ) ) 𝑦 ↔ ( 𝑥 ∈ ( V × V ) ∧ 𝑥 1st 𝑦 ) )
18 17 simplbi ( 𝑥 ( 1st ↾ ( V × V ) ) 𝑦𝑥 ∈ ( V × V ) )
19 18 adantr ( ( 𝑥 ( 1st ↾ ( V × V ) ) 𝑦𝑦 𝐴 𝑧 ) → 𝑥 ∈ ( V × V ) )
20 19 exlimiv ( ∃ 𝑦 ( 𝑥 ( 1st ↾ ( V × V ) ) 𝑦𝑦 𝐴 𝑧 ) → 𝑥 ∈ ( V × V ) )
21 15 20 sylbi ( 𝑥 ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) 𝑧𝑥 ∈ ( V × V ) )
22 21 adantr ( ( 𝑥 ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) 𝑧𝑥 ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) 𝑤 ) → 𝑥 ∈ ( V × V ) )
23 14 22 sylbi ( 𝑥 ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ⟨ 𝑧 , 𝑤 ⟩ → 𝑥 ∈ ( V × V ) )
24 10 23 sylbir ( ⟨ 𝑥 , ⟨ 𝑧 , 𝑤 ⟩ ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑥 ∈ ( V × V ) )
25 9 24 syl6bi ( 𝑦 = ⟨ 𝑧 , 𝑤 ⟩ → ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑥 ∈ ( V × V ) ) )
26 25 exlimivv ( ∃ 𝑧𝑤 𝑦 = ⟨ 𝑧 , 𝑤 ⟩ → ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑥 ∈ ( V × V ) ) )
27 7 26 sylbi ( 𝑦 ∈ ( V × V ) → ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑥 ∈ ( V × V ) ) )
28 6 27 mpcom ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → 𝑥 ∈ ( V × V ) )
29 28 6 opelxpd ( ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) → ⟨ 𝑥 , 𝑦 ⟩ ∈ ( ( V × V ) × ( V × V ) ) )
30 2 29 relssi ( ( 𝐴 ∘ ( 1st ↾ ( V × V ) ) ) ⊗ ( 𝐵 ∘ ( 2nd ↾ ( V × V ) ) ) ) ⊆ ( ( V × V ) × ( V × V ) )
31 1 30 eqsstri pprod ( 𝐴 , 𝐵 ) ⊆ ( ( V × V ) × ( V × V ) )