Metamath Proof Explorer


Theorem nfralwOLD

Description: Obsolete version of nfralw as of 13-Dec-2024. (Contributed by NM, 1-Sep-1999) (Revised by Gino Giotto, 10-Jan-2024) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypotheses nfralw.1 𝑥 𝐴
nfralw.2 𝑥 𝜑
Assertion nfralwOLD 𝑥𝑦𝐴 𝜑

Proof

Step Hyp Ref Expression
1 nfralw.1 𝑥 𝐴
2 nfralw.2 𝑥 𝜑
3 nftru 𝑦
4 1 a1i ( ⊤ → 𝑥 𝐴 )
5 2 a1i ( ⊤ → Ⅎ 𝑥 𝜑 )
6 3 4 5 nfraldw ( ⊤ → Ⅎ 𝑥𝑦𝐴 𝜑 )
7 6 mptru 𝑥𝑦𝐴 𝜑