Theorem nfnel 2612

Description: Bound-variable hypothesis builder for inequality. (Contributed by David Abernethy, 26-Jun-2011.) (Revised by Mario Carneiro, 7-Oct-2016.)

Hypotheses

Ref	Expression
nfnel.1	|- F/_xA
nfnel.2	|- F/_xB

Assertion

Ref	Expression
nfnel	|- F/x A e/ B

Proof of Theorem nfnel

Step	Hyp	Ref	Expression
1		df-nel 2520	. 2 |- (A e/ B <-> -. A e. B)
2		nfnel.1	. . . 4 |- F/_xA
3		nfnel.2	. . . 4 |- F/_xB
4	2, 3	nfel 2498	. . 3 |- F/x A e. B
5	4	nfn 1793	. 2 |- F/x -. A e. B
6	1, 5	nfxfr 1570	1 |- F/x A e/ B

Syntax hints:  -. wn 3   F/wnf 1544   e. wcel 1710   F/_wnfc 2477   e/ wnel 2518

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334

This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-cleq 2346  df-clel 2349  df-nfc 2479  df-nel 2520

This theorem is referenced by: (None)