Metamath Proof Explorer


Theorem cbvoprab12davw

Description: Change the first and second bound variables in an operation abstraction. Deduction form. (Contributed by GG, 14-Aug-2025)

Ref Expression
Hypothesis cbvoprab12davw.1 ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ( 𝜓𝜒 ) )
Assertion cbvoprab12davw ( 𝜑 → { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 } = { ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∣ 𝜒 } )

Proof

Step Hyp Ref Expression
1 cbvoprab12davw.1 ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ( 𝜓𝜒 ) )
2 simplr ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → 𝑥 = 𝑤 )
3 simpr ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → 𝑦 = 𝑣 )
4 2 3 opeq12d ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ⟨ 𝑥 , 𝑦 ⟩ = ⟨ 𝑤 , 𝑣 ⟩ )
5 4 opeq1d ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ )
6 5 eqeq2d ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ↔ 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ) )
7 6 1 anbi12d ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ( ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) ↔ ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) ) )
8 7 exbidv ( ( ( 𝜑𝑥 = 𝑤 ) ∧ 𝑦 = 𝑣 ) → ( ∃ 𝑧 ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) ↔ ∃ 𝑧 ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) ) )
9 8 cbvexdvaw ( ( 𝜑𝑥 = 𝑤 ) → ( ∃ 𝑦𝑧 ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) ↔ ∃ 𝑣𝑧 ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) ) )
10 9 cbvexdvaw ( 𝜑 → ( ∃ 𝑥𝑦𝑧 ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) ↔ ∃ 𝑤𝑣𝑧 ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) ) )
11 10 abbidv ( 𝜑 → { 𝑡 ∣ ∃ 𝑥𝑦𝑧 ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) } = { 𝑡 ∣ ∃ 𝑤𝑣𝑧 ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) } )
12 df-oprab { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 } = { 𝑡 ∣ ∃ 𝑥𝑦𝑧 ( 𝑡 = ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∧ 𝜓 ) }
13 df-oprab { ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∣ 𝜒 } = { 𝑡 ∣ ∃ 𝑤𝑣𝑧 ( 𝑡 = ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∧ 𝜒 ) }
14 11 12 13 3eqtr4g ( 𝜑 → { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 } = { ⟨ ⟨ 𝑤 , 𝑣 ⟩ , 𝑧 ⟩ ∣ 𝜒 } )