Metamath Proof Explorer


Theorem fnoprab

Description: Functionality and domain of an operation class abstraction. (Contributed by NM, 15-May-1995)

Ref Expression
Hypothesis fnoprab.1 ( 𝜑 → ∃! 𝑧 𝜓 )
Assertion fnoprab { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ ( 𝜑𝜓 ) } Fn { ⟨ 𝑥 , 𝑦 ⟩ ∣ 𝜑 }

Proof

Step Hyp Ref Expression
1 fnoprab.1 ( 𝜑 → ∃! 𝑧 𝜓 )
2 1 gen2 𝑥𝑦 ( 𝜑 → ∃! 𝑧 𝜓 )
3 fnoprabg ( ∀ 𝑥𝑦 ( 𝜑 → ∃! 𝑧 𝜓 ) → { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ ( 𝜑𝜓 ) } Fn { ⟨ 𝑥 , 𝑦 ⟩ ∣ 𝜑 } )
4 2 3 ax-mp { ⟨ ⟨ 𝑥 , 𝑦 ⟩ , 𝑧 ⟩ ∣ ( 𝜑𝜓 ) } Fn { ⟨ 𝑥 , 𝑦 ⟩ ∣ 𝜑 }