Theorem nfreudxy 2483

Description: Not-free deduction for restricted uniqueness. This is a version where x and y are distinct. (Contributed by Jim Kingdon, 6-Jun-2018.)

Hypotheses

Ref	Expression
nfreudxy.1	|- F/ y ph
nfreudxy.2	|- ( ph -> F/_ x A )
nfreudxy.3	|- ( ph -> F/ x ps )

Assertion

Ref	Expression
nfreudxy	|- ( ph -> F/ x E! y e. A ps )

Distinct variable group:   x, y

Allowed substitution hints:   ph( x, y)   ps( x, y)   A( x, y)

Proof of Theorem nfreudxy

Step	Hyp	Ref	Expression
1		nfreudxy.1	. . 3 |- F/ y ph
2		nfcv 2178	. . . . . 6 |- F/_ x y
3	2	a1i 9	. . . . 5 |- ( ph -> F/_ x y )
4		nfreudxy.2	. . . . 5 |- ( ph -> F/_ x A )
5	3, 4	nfeld 2193	. . . 4 |- ( ph -> F/ x y e. A )
6		nfreudxy.3	. . . 4 |- ( ph -> F/ x ps )
7	5, 6	nfand 1460	. . 3 |- ( ph -> F/ x ( y e. A /\ ps ) )
8	1, 7	nfeud 1916	. 2 |- ( ph -> F/ x E! y ( y e. A /\ ps ) )
9		df-reu 2313	. . 3 |- ( E! y e. A ps <-> E! y ( y e. A /\ ps ) )
10	9	nfbii 1362	. 2 |- ( F/ x E! y e. A ps <-> F/ x E! y ( y e. A /\ ps ) )
11	8, 10	sylibr 137	1 |- ( ph -> F/ x E! y e. A ps )

Syntax hints:   -> wi 4   /\ wa 97   F/wnf 1349   e. wcel 1393   E!weu 1900   F/_wnfc 2165   E!wreu 2308

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022

This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-eu 1903  df-cleq 2033  df-clel 2036  df-nfc 2167  df-reu 2313

This theorem is referenced by:  nfreuxy  2484