Theorem nfned 3120

Description: Bound-variable hypothesis builder for inequality. (Contributed by NM, 10-Nov-2007.) (Revised by Mario Carneiro, 7-Oct-2016.)

Hypotheses

Ref	Expression
nfned.1	⊢ (𝜑 → Ⅎ𝑥𝐴)
nfned.2	⊢ (𝜑 → Ⅎ𝑥𝐵)

Assertion

Ref	Expression
nfned	⊢ (𝜑 → Ⅎ𝑥 𝐴 ≠ 𝐵)

Proof of Theorem nfned

Step	Hyp	Ref	Expression
1		df-ne 3017	. 2 ⊢ (𝐴 ≠ 𝐵 ↔ ¬ 𝐴 = 𝐵)
2		nfned.1	. . . 4 ⊢ (𝜑 → Ⅎ𝑥𝐴)
3		nfned.2	. . . 4 ⊢ (𝜑 → Ⅎ𝑥𝐵)
4	2, 3	nfeqd 2988	. . 3 ⊢ (𝜑 → Ⅎ𝑥 𝐴 = 𝐵)
5	4	nfnd 1858	. 2 ⊢ (𝜑 → Ⅎ𝑥 ¬ 𝐴 = 𝐵)
6	1, 5	nfxfrd 1854	1 ⊢ (𝜑 → Ⅎ𝑥 𝐴 ≠ 𝐵)

Syntax hints:  ¬ wn 3   → wi 4   = wceq 1537  Ⅎwnf 1784  Ⅎwnfc 2961   ≠ wne 3016

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2793

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-ex 1781  df-nf 1785  df-cleq 2814  df-nfc 2963  df-ne 3017

This theorem is referenced by: (None)