MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  eximdOLD Structured version   Visualization version   GIF version

Theorem eximdOLD 2197
Description: Obsolete proof of eximd 2085 as of 6-Oct-2021. (Contributed by NM, 29-Jun-1993.) (Revised by Mario Carneiro, 24-Sep-2016.) (Proof modification is discouraged.) (New usage is discouraged.)
Hypotheses
Ref Expression
eximdOLD.1 𝑥𝜑
eximdOLD.2 (𝜑 → (𝜓𝜒))
Assertion
Ref Expression
eximdOLD (𝜑 → (∃𝑥𝜓 → ∃𝑥𝜒))

Proof of Theorem eximdOLD
StepHypRef Expression
1 eximdOLD.1 . . 3 𝑥𝜑
21nfriOLD 2189 . 2 (𝜑 → ∀𝑥𝜑)
3 eximdOLD.2 . 2 (𝜑 → (𝜓𝜒))
42, 3eximdh 1791 1 (𝜑 → (∃𝑥𝜓 → ∃𝑥𝜒))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wex 1704  wnfOLD 1709
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-12 2047
This theorem depends on definitions:  df-bi 197  df-ex 1705  df-nfOLD 1721
This theorem is referenced by:  exlimdOLD  2223
  Copyright terms: Public domain W3C validator