Metamath Proof Explorer


Theorem exdistr2

Description: Distribution of existential quantifiers. (Contributed by NM, 17-Mar-1995)

Ref Expression
Assertion exdistr2 ( ∃ 𝑥 ∃ 𝑦 ∃ 𝑧 ( 𝜑 ∧ 𝜓 ) ↔ ∃ 𝑥 ( 𝜑 ∧ ∃ 𝑦 ∃ 𝑧 𝜓 ) )

Proof

Step Hyp Ref Expression
1 19.42vv ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝜑 ∧ 𝜓 ) ↔ ( 𝜑 ∧ ∃ 𝑦 ∃ 𝑧 𝜓 ) )
2 1 exbii ⊢ ( ∃ 𝑥 ∃ 𝑦 ∃ 𝑧 ( 𝜑 ∧ 𝜓 ) ↔ ∃ 𝑥 ( 𝜑 ∧ ∃ 𝑦 ∃ 𝑧 𝜓 ) )