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

Theorem nfvdOLD 1859
Description: Obsolete proof of nfvd 1831 as of 6-Oct-2021. (Contributed by Mario Carneiro, 6-Oct-2016.) (New usage is discouraged.) (Proof modification is discouraged.)
Assertion
Ref Expression
nfvdOLD (𝜑 → Ⅎ𝑥𝜓)
Distinct variable group:   𝜓,𝑥
Allowed substitution hint:   𝜑(𝑥)

Proof of Theorem nfvdOLD
StepHypRef Expression
1 nfvOLD 1858 . 2 𝑥𝜓
21a1i 11 1 (𝜑 → Ⅎ𝑥𝜓)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wnfOLD 1700
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-5 1827
This theorem depends on definitions:  df-bi 196  df-nfOLD 1712
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator