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Theorem setswith 4322
Description: Two ways to express the class of all sets that contain A. (Contributed by SF, 14-Jan-2015.)
Assertion
Ref Expression
setswith ⊢ {x ∣ A ∈ x} = if(A ∈ V, ( Sk “k {{A}}), ∅)
Distinct variable group:   x,A

Proof of Theorem setswith
Dummy variable y is distinct from all other variables.
StepHypRef Expression
1 snex 4112 . . . . . . 7 ⊢ {A} ∈ V
2 opkeq1 4060 . . . . . . . 8 ⊢ (y = {A} → ⟪y, x⟫ = ⟪{A}, x⟫)
32eleq1d 2419 . . . . . . 7 ⊢ (y = {A} → (⟪y, x⟫ ∈ Sk ↔ ⟪{A}, x⟫ ∈ Sk ))
41, 3rexsn 3769 . . . . . 6 ⊢ (∃y ∈ {{A}}⟪y, x⟫ ∈ Sk ↔ ⟪{A}, x⟫ ∈ Sk )
5 vex 2863 . . . . . . 7 ⊢ x ∈ V
6 elssetkg 4270 . . . . . . 7 ⊢ ((A ∈ V ∧ x ∈ V) → (⟪{A}, x⟫ ∈ Sk ↔ A ∈ x))
75, 6mpan2 652 . . . . . 6 ⊢ (A ∈ V → (⟪{A}, x⟫ ∈ Sk ↔ A ∈ x))
84, 7syl5rbb 249 . . . . 5 ⊢ (A ∈ V → (A ∈ x ↔ ∃y ∈ {{A}}⟪y, x⟫ ∈ Sk ))
98abbidv 2468 . . . 4 ⊢ (A ∈ V → {x ∣ A ∈ x} = {x ∣ ∃y ∈ {{A}}⟪y, x⟫ ∈ Sk })
10 df-imak 4190 . . . 4 ⊢ ( Sk “k {{A}}) = {x ∣ ∃y ∈ {{A}}⟪y, x⟫ ∈ Sk }
119, 10syl6eqr 2403 . . 3 ⊢ (A ∈ V → {x ∣ A ∈ x} = ( Sk “k {{A}}))
12 iftrue 3669 . . 3 ⊢ (A ∈ V → if(A ∈ V, ( Sk “k {{A}}), ∅) = ( Sk “k {{A}}))
1311, 12eqtr4d 2388 . 2 ⊢ (A ∈ V → {x ∣ A ∈ x} = if(A ∈ V, ( Sk “k {{A}}), ∅))
14 elex 2868 . . . . . 6 ⊢ (A ∈ x → A ∈ V)
1514con3i 127 . . . . 5 ⊢ (¬ A ∈ V → ¬ A ∈ x)
1615alrimiv 1631 . . . 4 ⊢ (¬ A ∈ V → ∀x ¬ A ∈ x)
17 ab0 3570 . . . 4 ⊢ ({x ∣ A ∈ x} = ∅ ↔ ∀x ¬ A ∈ x)
1816, 17sylibr 203 . . 3 ⊢ (¬ A ∈ V → {x ∣ A ∈ x} = ∅)
19 iffalse 3670 . . 3 ⊢ (¬ A ∈ V → if(A ∈ V, ( Sk “k {{A}}), ∅) = ∅)
2018, 19eqtr4d 2388 . 2 ⊢ (¬ A ∈ V → {x ∣ A ∈ x} = if(A ∈ V, ( Sk “k {{A}}), ∅))
2113, 20pm2.61i 156 1 ⊢ {x ∣ A ∈ x} = if(A ∈ V, ( Sk “k {{A}}), ∅)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  ¬ wn 3   ↔ wb 176  ∀wal 1540   = wceq 1642   ∈ wcel 1710  {cab 2339  ∃wrex 2616  Vcvv 2860  ∅c0 3551   ifcif 3663  {csn 3738  ⟪copk 4058   “k cimak 4180   Sk cssetk 4184
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4079  ax-sn 4088
This proof depends on definitions:  df-bi 177  df-or 359  df-an 360  df-3an 936  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2479  df-ne 2519  df-rex 2621  df-v 2862  df-sbc 3048  df-nin 3212  df-compl 3213  df-in 3214  df-un 3215  df-dif 3216  df-ss 3260  df-nul 3552  df-if 3664  df-sn 3742  df-pr 3743  df-opk 4059  df-imak 4190  df-ssetk 4194
This theorem is used by:  setswithex  4323
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