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Theorem pweq 3619
Description: Equality theorem for power class. (Contributed by NM, 5-Aug-1993.)
Assertion
Ref Expression
pweq  |-  ( A  =  B  ->  ~P A  =  ~P B
)

Proof of Theorem pweq
Dummy variable  x is distinct from all other variables.
StepHypRef Expression
1 sseq2 3217 . . 3  |-  ( A  =  B  ->  (
x  C_  A  <->  x  C_  B
) )
21abbidv 2323 . 2  |-  ( A  =  B  ->  { x  |  x  C_  A }  =  { x  |  x 
C_  B } )
3 df-pw 3618 . 2  |-  ~P A  =  { x  |  x 
C_  A }
4 df-pw 3618 . 2  |-  ~P B  =  { x  |  x 
C_  B }
52, 3, 43eqtr4g 2263 1  |-  ( A  =  B  ->  ~P A  =  ~P B
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    = wceq 1373   {cab 2191    C_ wss 3166   ~Pcpw 3616
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-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-11 1529  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187
This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-in 3172  df-ss 3179  df-pw 3618
This theorem is referenced by:  pweqi  3620  pweqd  3621  axpweq  4215  pwexg  4224  pwssunim  4331  ordpwsucexmid  4618  exmidpw2en  7009  fival  7072  isacnm  7315  istopg  14471  istopon  14485  eltg  14524  tgdom  14544  ntrval  14582
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