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Theorem sspw1or2 7544
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 2214 . . . . . 6  |-  ( s  =  x  ->  (
j  e.  s  <->  j  e.  x ) )
21exbidv 1878 . . . . 5  |-  ( s  =  x  ->  ( E. j  j  e.  s 
<->  E. j  j  e.  x ) )
32elrab 2982 . . . 4  |-  ( x  e.  { s  e. 
~P V  |  E. j  j  e.  s } 
<->  ( x  e.  ~P V  /\  E. j  j  e.  x ) )
43anbi1i 462 . . 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 7092 . . . . . 6  |-  ( x 
~~  1o  ->  E. j 
j  e.  x )
6 en2m 7113 . . . . . 6  |-  ( x 
~~  2o  ->  E. j 
j  e.  x )
75, 6jaoi 728 . . . . 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 459 . . 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 2806 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
This proof depends on syntax axioms:    /\ wa 104    \/ wo 720    = wceq 1402   E.wex 1545    e. wcel 2209   {crab 2532   ~Pcpw 3688   class class class wbr 4130   1oc1o 6680   2oc2o 6681    ~~ cen 7020
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578
This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4131  df-opab 4193  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-suc 4516  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-1o 6687  df-2o 6688  df-en 7023
This theorem is used by:  subupgr  16514
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