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Theorem sspw1or2 7508
Description: The set of subsets of a given set with one or two elements can be expressed as elements of the power set or as inhabited elements of the power set. (Contributed by Jim Kingdon, 31-Mar-2026.)
Assertion
Ref Expression
sspw1or2  |-  { x  e.  { s  e.  ~P V  |  E. j 
j  e.  s }  |  ( x  ~~  1o  \/  x  ~~  2o ) }  =  {
x  e.  ~P V  |  ( x  ~~  1o  \/  x  ~~  2o ) }
Distinct variable groups:    V, s    j,
s, x
Allowed substitution hints:    V( x, j)

Proof of Theorem sspw1or2
StepHypRef Expression
1 elequ2 2210 . . . . . 6  |-  ( s  =  x  ->  (
j  e.  s  <->  j  e.  x ) )
21exbidv 1874 . . . . 5  |-  ( s  =  x  ->  ( E. j  j  e.  s 
<->  E. j  j  e.  x ) )
32elrab 2976 . . . 4  |-  ( x  e.  { s  e. 
~P V  |  E. j  j  e.  s } 
<->  ( x  e.  ~P V  /\  E. j  j  e.  x ) )
43anbi1i 458 . . 3  |-  ( ( x  e.  { s  e.  ~P V  |  E. j  j  e.  s }  /\  (
x  ~~  1o  \/  x  ~~  2o ) )  <-> 
( ( x  e. 
~P V  /\  E. j  j  e.  x
)  /\  ( x  ~~  1o  \/  x  ~~  2o ) ) )
5 en1m 7058 . . . . . 6  |-  ( x 
~~  1o  ->  E. j 
j  e.  x )
6 en2m 7079 . . . . . 6  |-  ( x 
~~  2o  ->  E. j 
j  e.  x )
75, 6jaoi 724 . . . . 5  |-  ( ( x  ~~  1o  \/  x  ~~  2o )  ->  E. j  j  e.  x )
87biantrud 304 . . . 4  |-  ( ( x  ~~  1o  \/  x  ~~  2o )  -> 
( x  e.  ~P V 
<->  ( x  e.  ~P V  /\  E. j  j  e.  x ) ) )
98pm5.32ri 455 . . 3  |-  ( ( x  e.  ~P V  /\  ( x  ~~  1o  \/  x  ~~  2o ) )  <->  ( ( x  e.  ~P V  /\  E. j  j  e.  x
)  /\  ( x  ~~  1o  \/  x  ~~  2o ) ) )
104, 9bitr4i 187 . 2  |-  ( ( x  e.  { s  e.  ~P V  |  E. j  j  e.  s }  /\  (
x  ~~  1o  \/  x  ~~  2o ) )  <-> 
( x  e.  ~P V  /\  ( x  ~~  1o  \/  x  ~~  2o ) ) )
1110rabbia2 2800 1  |-  { x  e.  { s  e.  ~P V  |  E. j 
j  e.  s }  |  ( x  ~~  1o  \/  x  ~~  2o ) }  =  {
x  e.  ~P V  |  ( x  ~~  1o  \/  x  ~~  2o ) }
Colors of variables: wff set class
Syntax hints:    /\ wa 104    \/ wo 716    = wceq 1398   E.wex 1541    e. wcel 2205   {crab 2526   ~Pcpw 3674   class class class wbr 4114   1oc1o 6653   2oc2o 6654    ~~ cen 6986
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 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-sep 4233  ax-nul 4241  ax-pow 4292  ax-pr 4327  ax-un 4559
This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ral 2527  df-rex 2528  df-reu 2529  df-rab 2531  df-v 2817  df-sbc 3046  df-dif 3216  df-un 3218  df-in 3220  df-ss 3227  df-nul 3513  df-pw 3676  df-sn 3700  df-pr 3701  df-op 3703  df-uni 3920  df-br 4115  df-opab 4177  df-tr 4214  df-id 4419  df-iord 4492  df-on 4494  df-suc 4497  df-xp 4760  df-rel 4761  df-cnv 4762  df-co 4763  df-dm 4764  df-rn 4765  df-res 4766  df-ima 4767  df-iota 5317  df-fun 5359  df-fn 5360  df-f 5361  df-f1 5362  df-fo 5363  df-f1o 5364  df-fv 5365  df-1o 6660  df-2o 6661  df-en 6989
This theorem is referenced by:  subupgr  16394
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