Metamath Proof Explorer


Theorem cbvmpovw2

Description: Change bound variables and domains in a maps-to function, using implicit substitution. (Contributed by GG, 14-Aug-2025)

Ref Expression
Hypotheses cbvmpovw2.1 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐸 = 𝐹 )
cbvmpovw2.2 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐶 = 𝐷 )
cbvmpovw2.3 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐴 = 𝐵 )
Assertion cbvmpovw2 ( 𝑥𝐴 , 𝑦𝐶𝐸 ) = ( 𝑧𝐵 , 𝑤𝐷𝐹 )

Proof

Step Hyp Ref Expression
1 cbvmpovw2.1 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐸 = 𝐹 )
2 cbvmpovw2.2 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐶 = 𝐷 )
3 cbvmpovw2.3 ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝐴 = 𝐵 )
4 simpl ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝑥 = 𝑧 )
5 4 3 eleq12d ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → ( 𝑥𝐴𝑧𝐵 ) )
6 simpr ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → 𝑦 = 𝑤 )
7 6 2 eleq12d ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → ( 𝑦𝐶𝑤𝐷 ) )
8 5 7 anbi12d ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → ( ( 𝑥𝐴𝑦𝐶 ) ↔ ( 𝑧𝐵𝑤𝐷 ) ) )
9 1 eqeq2d ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → ( 𝑡 = 𝐸𝑡 = 𝐹 ) )
10 8 9 anbi12d ( ( 𝑥 = 𝑧𝑦 = 𝑤 ) → ( ( ( 𝑥𝐴𝑦𝐶 ) ∧ 𝑡 = 𝐸 ) ↔ ( ( 𝑧𝐵𝑤𝐷 ) ∧ 𝑡 = 𝐹 ) ) )
11 10 cbvoprab12v { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑡 ⟩ ∣ ( ( 𝑥𝐴𝑦𝐶 ) ∧ 𝑡 = 𝐸 ) } = { ⟨ ⟨ 𝑧 , 𝑤 ⟩ , 𝑡 ⟩ ∣ ( ( 𝑧𝐵𝑤𝐷 ) ∧ 𝑡 = 𝐹 ) }
12 df-mpo ( 𝑥𝐴 , 𝑦𝐶𝐸 ) = { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑡 ⟩ ∣ ( ( 𝑥𝐴𝑦𝐶 ) ∧ 𝑡 = 𝐸 ) }
13 df-mpo ( 𝑧𝐵 , 𝑤𝐷𝐹 ) = { ⟨ ⟨ 𝑧 , 𝑤 ⟩ , 𝑡 ⟩ ∣ ( ( 𝑧𝐵𝑤𝐷 ) ∧ 𝑡 = 𝐹 ) }
14 11 12 13 3eqtr4i ( 𝑥𝐴 , 𝑦𝐶𝐸 ) = ( 𝑧𝐵 , 𝑤𝐷𝐹 )