MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  notabw Structured version   Visualization version   GIF version

Theorem notabw 4269
Description: A class abstraction defined by a negation. Version of notab 4270 using implicit substitution, which does not require ax-10 2179, ax-12 2216. (Contributed by GG, 15-Oct-2024.)
Hypothesis
Ref Expression
notabw.1 (𝑥 = 𝑦 → (𝜑𝜓))
Assertion
Ref Expression
notabw {𝑥 ∣ ¬ 𝜑} = (V ∖ {𝑦𝜓})
Distinct variable groups:   𝑥,𝑦   𝜑,𝑦   𝜓,𝑥
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)

Proof of Theorem notabw
StepHypRef Expression
1 vex 3462 . . . . 5 𝑥 ∈ V
21biantrur 540 . . . 4 𝑥 ∈ {𝑦𝜓} ↔ (𝑥 ∈ V ∧ ¬ 𝑥 ∈ {𝑦𝜓}))
3 df-clab 2745 . . . . 5 (𝑥 ∈ {𝑦𝜓} ↔ [𝑥 / 𝑦]𝜓)
4 notabw.1 . . . . . . . 8 (𝑥 = 𝑦 → (𝜑𝜓))
54bicomd 226 . . . . . . 7 (𝑥 = 𝑦 → (𝜓𝜑))
65equcoms 2053 . . . . . 6 (𝑦 = 𝑥 → (𝜓𝜑))
76sbievw 2131 . . . . 5 ([𝑥 / 𝑦]𝜓𝜑)
83, 7bitri 278 . . . 4 (𝑥 ∈ {𝑦𝜓} ↔ 𝜑)
92, 8xchnxbi 335 . . 3 𝜑 ↔ (𝑥 ∈ V ∧ ¬ 𝑥 ∈ {𝑦𝜓}))
109abbii 2833 . 2 {𝑥 ∣ ¬ 𝜑} = {𝑥 ∣ (𝑥 ∈ V ∧ ¬ 𝑥 ∈ {𝑦𝜓})}
11 df-dif 3911 . 2 (V ∖ {𝑦𝜓}) = {𝑥 ∣ (𝑥 ∈ V ∧ ¬ 𝑥 ∈ {𝑦𝜓})}
1210, 11eqtr4i 2792 1 {𝑥 ∣ ¬ 𝜑} = (V ∖ {𝑦𝜓})
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  ¬ wn 3  wi 4  wb 209  wa 401   = wceq 1570  [wsb 2099  wcel 2146  {cab 2744  Vcvv 3458  cdif 3905
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-ext 2738
This proof depends on definitions:  df-bi 210  df-an 402  df-tru 1573  df-ex 1813  df-sb 2100  df-clab 2745  df-cleq 2758  df-clel 2841  df-v 3460  df-dif 3911
This theorem is used by:  dfif3  4507
  Copyright terms: Public domain W3C validator