Metamath Proof Explorer


Theorem nfan1c

Description: Variant of nfan and commuted form of nfan1 . (Contributed by BTernaryTau, 31-Jul-2025)

Ref Expression
Hypotheses nfan1c.1 ⊢ Ⅎ 𝑥 𝜑
nfan1c.2 ⊢ ( 𝜑 → Ⅎ 𝑥 𝜓 )
Assertion nfan1c Ⅎ 𝑥 ( 𝜓 ∧ 𝜑 )

Proof

Step Hyp Ref Expression
1 nfan1c.1 ⊢ Ⅎ 𝑥 𝜑
2 nfan1c.2 ⊢ ( 𝜑 → Ⅎ 𝑥 𝜓 )
3 1 2 nfan1 ⊢ Ⅎ 𝑥 ( 𝜑 ∧ 𝜓 )
4 ancom ⊢ ( ( 𝜑 ∧ 𝜓 ) ↔ ( 𝜓 ∧ 𝜑 ) )
5 4 nfbii ⊢ ( Ⅎ 𝑥 ( 𝜑 ∧ 𝜓 ) ↔ Ⅎ 𝑥 ( 𝜓 ∧ 𝜑 ) )
6 3 5 mpbi ⊢ Ⅎ 𝑥 ( 𝜓 ∧ 𝜑 )