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Theorem acexmidlema 5503
Description: Lemma for acexmid 5511. (Contributed by Jim Kingdon, 6-Aug-2019.)
Hypotheses
Ref Expression
acexmidlem.a  |-  A  =  { x  e.  { (/)
,  { (/) } }  |  ( x  =  (/)  \/  ph ) }
acexmidlem.b  |-  B  =  { x  e.  { (/)
,  { (/) } }  |  ( x  =  { (/) }  \/  ph ) }
acexmidlem.c  |-  C  =  { A ,  B }
Assertion
Ref Expression
acexmidlema  |-  ( {
(/) }  e.  A  ->  ph )
Distinct variable groups:    x, A    x, B    x, C    ph, x

Proof of Theorem acexmidlema
StepHypRef Expression
1 acexmidlem.a . . . 4  |-  A  =  { x  e.  { (/)
,  { (/) } }  |  ( x  =  (/)  \/  ph ) }
21eleq2i 2104 . . 3  |-  ( {
(/) }  e.  A  <->  {
(/) }  e.  { x  e.  { (/) ,  { (/) } }  |  ( x  =  (/)  \/  ph ) } )
3 p0ex 3939 . . . . 5  |-  { (/) }  e.  _V
43prid2 3477 . . . 4  |-  { (/) }  e.  { (/) ,  { (/)
} }
5 eqeq1 2046 . . . . . 6  |-  ( x  =  { (/) }  ->  ( x  =  (/)  <->  { (/) }  =  (/) ) )
65orbi1d 705 . . . . 5  |-  ( x  =  { (/) }  ->  ( ( x  =  (/)  \/ 
ph )  <->  ( { (/)
}  =  (/)  \/  ph ) ) )
76elrab3 2699 . . . 4  |-  ( {
(/) }  e.  { (/) ,  { (/) } }  ->  ( { (/) }  e.  {
x  e.  { (/) ,  { (/) } }  | 
( x  =  (/)  \/ 
ph ) }  <->  ( { (/)
}  =  (/)  \/  ph ) ) )
84, 7ax-mp 7 . . 3  |-  ( {
(/) }  e.  { x  e.  { (/) ,  { (/) } }  |  ( x  =  (/)  \/  ph ) } 
<->  ( { (/) }  =  (/) 
\/  ph ) )
92, 8bitri 173 . 2  |-  ( {
(/) }  e.  A  <->  ( { (/) }  =  (/)  \/ 
ph ) )
10 noel 3228 . . . 4  |-  -.  (/)  e.  (/)
11 0ex 3884 . . . . . 6  |-  (/)  e.  _V
1211snid 3402 . . . . 5  |-  (/)  e.  { (/)
}
13 eleq2 2101 . . . . 5  |-  ( {
(/) }  =  (/)  ->  ( (/) 
e.  { (/) }  <->  (/)  e.  (/) ) )
1412, 13mpbii 136 . . . 4  |-  ( {
(/) }  =  (/)  ->  (/)  e.  (/) )
1510, 14mto 588 . . 3  |-  -.  { (/)
}  =  (/)
16 orel1 644 . . 3  |-  ( -. 
{ (/) }  =  (/)  ->  ( ( { (/) }  =  (/)  \/  ph )  ->  ph ) )
1715, 16ax-mp 7 . 2  |-  ( ( { (/) }  =  (/)  \/ 
ph )  ->  ph )
189, 17sylbi 114 1  |-  ( {
(/) }  e.  A  ->  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    <-> wb 98    \/ wo 629    = wceq 1243    e. wcel 1393   {crab 2310   (/)c0 3224   {csn 3375   {cpr 3376
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-in1 544  ax-in2 545  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-14 1405  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022  ax-sep 3875  ax-nul 3883  ax-pow 3927
This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-rab 2315  df-v 2559  df-dif 2920  df-un 2922  df-in 2924  df-ss 2931  df-nul 3225  df-pw 3361  df-sn 3381  df-pr 3382
This theorem is referenced by:  acexmidlem1  5508
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