Metamath Proof Explorer


Theorem rexlimiv

Description: Inference from Theorem 19.23 of Margaris p. 90. (Restricted quantifier version.) (Contributed by NM, 20-Nov-1994) Reduce dependencies on axioms. (Revised by Wolf Lammen, 14-Jan-2020)

Ref Expression
Hypothesis rexlimiv.1 ( 𝑥𝐴 → ( 𝜑𝜓 ) )
Assertion rexlimiv ( ∃ 𝑥𝐴 𝜑𝜓 )

Proof

Step Hyp Ref Expression
1 rexlimiv.1 ( 𝑥𝐴 → ( 𝜑𝜓 ) )
2 1 rgen 𝑥𝐴 ( 𝜑𝜓 )
3 r19.23v ( ∀ 𝑥𝐴 ( 𝜑𝜓 ) ↔ ( ∃ 𝑥𝐴 𝜑𝜓 ) )
4 2 3 mpbi ( ∃ 𝑥𝐴 𝜑𝜓 )