ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  pweq GIF version

Theorem pweq 3562
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 3166 . . 3 (𝐴 = 𝐵 → (𝑥𝐴𝑥𝐵))
21abbidv 2284 . 2 (𝐴 = 𝐵 → {𝑥𝑥𝐴} = {𝑥𝑥𝐵})
3 df-pw 3561 . 2 𝒫 𝐴 = {𝑥𝑥𝐴}
4 df-pw 3561 . 2 𝒫 𝐵 = {𝑥𝑥𝐵}
52, 3, 43eqtr4g 2224 1 (𝐴 = 𝐵 → 𝒫 𝐴 = 𝒫 𝐵)
Colors of variables: wff set class
Syntax hints:  wi 4   = wceq 1343  {cab 2151  wss 3116  𝒫 cpw 3559
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-11 1494  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-in 3122  df-ss 3129  df-pw 3561
This theorem is referenced by:  pweqi  3563  pweqd  3564  axpweq  4150  pwexg  4159  pwssunim  4262  ordpwsucexmid  4547  fival  6935  istopg  12647  istopon  12661  eltg  12702  tgdom  12722  ntrval  12760
  Copyright terms: Public domain W3C validator