Metamath Proof Explorer


Theorem ssoprab2i

Description: Inference of operation class abstraction subclass from implication. (Contributed by NM, 11-Nov-1995) (Revised by David Abernethy, 19-Jun-2012)

Ref Expression
Hypothesis ssoprab2i.1 ( 𝜑𝜓 )
Assertion ssoprab2i { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜑 } ⊆ { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 }

Proof

Step Hyp Ref Expression
1 ssoprab2i.1 ( 𝜑𝜓 )
2 1 anim2i ( ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜑 ) → ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜓 ) )
3 2 2eximi ( ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜑 ) → ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜓 ) )
4 3 ssopab2i { ⟨ 𝑤 , 𝑧 ⟩ ∣ ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜑 ) } ⊆ { ⟨ 𝑤 , 𝑧 ⟩ ∣ ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜓 ) }
5 dfoprab2 { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜑 } = { ⟨ 𝑤 , 𝑧 ⟩ ∣ ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜑 ) }
6 dfoprab2 { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 } = { ⟨ 𝑤 , 𝑧 ⟩ ∣ ∃ 𝑥𝑦 ( 𝑤 = ⟨ 𝑥 , 𝑦 ⟩ ∧ 𝜓 ) }
7 4 5 6 3sstr4i { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜑 } ⊆ { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ 𝜓 }