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Theorem acexmidlema 5882
Description: Lemma for acexmid 5890. (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 2256 . . 3  |-  ( {
(/) }  e.  A  <->  {
(/) }  e.  { x  e.  { (/) ,  { (/) } }  |  ( x  =  (/)  \/  ph ) } )
3 p0ex 4203 . . . . 5  |-  { (/) }  e.  _V
43prid2 3714 . . . 4  |-  { (/) }  e.  { (/) ,  { (/)
} }
5 eqeq1 2196 . . . . . 6  |-  ( x  =  { (/) }  ->  ( x  =  (/)  <->  { (/) }  =  (/) ) )
65orbi1d 792 . . . . 5  |-  ( x  =  { (/) }  ->  ( ( x  =  (/)  \/ 
ph )  <->  ( { (/)
}  =  (/)  \/  ph ) ) )
76elrab3 2909 . . . 4  |-  ( {
(/) }  e.  { (/) ,  { (/) } }  ->  ( { (/) }  e.  {
x  e.  { (/) ,  { (/) } }  | 
( x  =  (/)  \/ 
ph ) }  <->  ( { (/)
}  =  (/)  \/  ph ) ) )
84, 7ax-mp 5 . . 3  |-  ( {
(/) }  e.  { x  e.  { (/) ,  { (/) } }  |  ( x  =  (/)  \/  ph ) } 
<->  ( { (/) }  =  (/) 
\/  ph ) )
92, 8bitri 184 . 2  |-  ( {
(/) }  e.  A  <->  ( { (/) }  =  (/)  \/ 
ph ) )
10 noel 3441 . . . 4  |-  -.  (/)  e.  (/)
11 0ex 4145 . . . . . 6  |-  (/)  e.  _V
1211snid 3638 . . . . 5  |-  (/)  e.  { (/)
}
13 eleq2 2253 . . . . 5  |-  ( {
(/) }  =  (/)  ->  ( (/) 
e.  { (/) }  <->  (/)  e.  (/) ) )
1412, 13mpbii 148 . . . 4  |-  ( {
(/) }  =  (/)  ->  (/)  e.  (/) )
1510, 14mto 663 . . 3  |-  -.  { (/)
}  =  (/)
16 orel1 726 . . 3  |-  ( -. 
{ (/) }  =  (/)  ->  ( ( { (/) }  =  (/)  \/  ph )  ->  ph ) )
1715, 16ax-mp 5 . 2  |-  ( ( { (/) }  =  (/)  \/ 
ph )  ->  ph )
189, 17sylbi 121 1  |-  ( {
(/) }  e.  A  ->  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    <-> wb 105    \/ wo 709    = wceq 1364    e. wcel 2160   {crab 2472   (/)c0 3437   {csn 3607   {cpr 3608
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-14 2163  ax-ext 2171  ax-sep 4136  ax-nul 4144  ax-pow 4189
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2176  df-cleq 2182  df-clel 2185  df-nfc 2321  df-rab 2477  df-v 2754  df-dif 3146  df-un 3148  df-in 3150  df-ss 3157  df-nul 3438  df-pw 3592  df-sn 3613  df-pr 3614
This theorem is referenced by:  acexmidlem1  5887
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