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Theorem intab 3807
 Description: The intersection of a special case of a class abstraction. 𝑦 may be free in 𝜑 and 𝐴, which can be thought of a 𝜑(𝑦) and 𝐴(𝑦). (Contributed by NM, 28-Jul-2006.) (Proof shortened by Mario Carneiro, 14-Nov-2016.)
Hypotheses
Ref Expression
intab.1 𝐴 ∈ V
intab.2 {𝑥 ∣ ∃𝑦(𝜑𝑥 = 𝐴)} ∈ V
Assertion
Ref Expression
intab {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} = {𝑥 ∣ ∃𝑦(𝜑𝑥 = 𝐴)}
Distinct variable groups:   𝑥,𝐴   𝜑,𝑥   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑦)   𝐴(𝑦)

Proof of Theorem intab
Dummy variable 𝑧 is distinct from all other variables.
StepHypRef Expression
1 eqeq1 2147 . . . . . . . . . 10 (𝑧 = 𝑥 → (𝑧 = 𝐴𝑥 = 𝐴))
21anbi2d 460 . . . . . . . . 9 (𝑧 = 𝑥 → ((𝜑𝑧 = 𝐴) ↔ (𝜑𝑥 = 𝐴)))
32exbidv 1798 . . . . . . . 8 (𝑧 = 𝑥 → (∃𝑦(𝜑𝑧 = 𝐴) ↔ ∃𝑦(𝜑𝑥 = 𝐴)))
43cbvabv 2265 . . . . . . 7 {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} = {𝑥 ∣ ∃𝑦(𝜑𝑥 = 𝐴)}
5 intab.2 . . . . . . 7 {𝑥 ∣ ∃𝑦(𝜑𝑥 = 𝐴)} ∈ V
64, 5eqeltri 2213 . . . . . 6 {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} ∈ V
7 nfe1 1473 . . . . . . . . 9 𝑦𝑦(𝜑𝑧 = 𝐴)
87nfab 2287 . . . . . . . 8 𝑦{𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}
98nfeq2 2294 . . . . . . 7 𝑦 𝑥 = {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}
10 eleq2 2204 . . . . . . . 8 (𝑥 = {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} → (𝐴𝑥𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}))
1110imbi2d 229 . . . . . . 7 (𝑥 = {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} → ((𝜑𝐴𝑥) ↔ (𝜑𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)})))
129, 11albid 1595 . . . . . 6 (𝑥 = {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} → (∀𝑦(𝜑𝐴𝑥) ↔ ∀𝑦(𝜑𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)})))
136, 12elab 2831 . . . . 5 ({𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} ∈ {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} ↔ ∀𝑦(𝜑𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}))
14 19.8a 1570 . . . . . . . . 9 ((𝜑𝑧 = 𝐴) → ∃𝑦(𝜑𝑧 = 𝐴))
1514ex 114 . . . . . . . 8 (𝜑 → (𝑧 = 𝐴 → ∃𝑦(𝜑𝑧 = 𝐴)))
1615alrimiv 1847 . . . . . . 7 (𝜑 → ∀𝑧(𝑧 = 𝐴 → ∃𝑦(𝜑𝑧 = 𝐴)))
17 intab.1 . . . . . . . 8 𝐴 ∈ V
1817sbc6 2937 . . . . . . 7 ([𝐴 / 𝑧]𝑦(𝜑𝑧 = 𝐴) ↔ ∀𝑧(𝑧 = 𝐴 → ∃𝑦(𝜑𝑧 = 𝐴)))
1916, 18sylibr 133 . . . . . 6 (𝜑[𝐴 / 𝑧]𝑦(𝜑𝑧 = 𝐴))
20 df-sbc 2913 . . . . . 6 ([𝐴 / 𝑧]𝑦(𝜑𝑧 = 𝐴) ↔ 𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)})
2119, 20sylib 121 . . . . 5 (𝜑𝐴 ∈ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)})
2213, 21mpgbir 1430 . . . 4 {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} ∈ {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)}
23 intss1 3793 . . . 4 ({𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} ∈ {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} → {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} ⊆ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)})
2422, 23ax-mp 5 . . 3 {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} ⊆ {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}
25 19.29r 1601 . . . . . . . 8 ((∃𝑦(𝜑𝑧 = 𝐴) ∧ ∀𝑦(𝜑𝐴𝑥)) → ∃𝑦((𝜑𝑧 = 𝐴) ∧ (𝜑𝐴𝑥)))
26 simplr 520 . . . . . . . . . 10 (((𝜑𝑧 = 𝐴) ∧ (𝜑𝐴𝑥)) → 𝑧 = 𝐴)
27 pm3.35 345 . . . . . . . . . . 11 ((𝜑 ∧ (𝜑𝐴𝑥)) → 𝐴𝑥)
2827adantlr 469 . . . . . . . . . 10 (((𝜑𝑧 = 𝐴) ∧ (𝜑𝐴𝑥)) → 𝐴𝑥)
2926, 28eqeltrd 2217 . . . . . . . . 9 (((𝜑𝑧 = 𝐴) ∧ (𝜑𝐴𝑥)) → 𝑧𝑥)
3029exlimiv 1578 . . . . . . . 8 (∃𝑦((𝜑𝑧 = 𝐴) ∧ (𝜑𝐴𝑥)) → 𝑧𝑥)
3125, 30syl 14 . . . . . . 7 ((∃𝑦(𝜑𝑧 = 𝐴) ∧ ∀𝑦(𝜑𝐴𝑥)) → 𝑧𝑥)
3231ex 114 . . . . . 6 (∃𝑦(𝜑𝑧 = 𝐴) → (∀𝑦(𝜑𝐴𝑥) → 𝑧𝑥))
3332alrimiv 1847 . . . . 5 (∃𝑦(𝜑𝑧 = 𝐴) → ∀𝑥(∀𝑦(𝜑𝐴𝑥) → 𝑧𝑥))
34 vex 2692 . . . . . 6 𝑧 ∈ V
3534elintab 3789 . . . . 5 (𝑧 {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} ↔ ∀𝑥(∀𝑦(𝜑𝐴𝑥) → 𝑧𝑥))
3633, 35sylibr 133 . . . 4 (∃𝑦(𝜑𝑧 = 𝐴) → 𝑧 {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)})
3736abssi 3176 . . 3 {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)} ⊆ {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)}
3824, 37eqssi 3117 . 2 {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} = {𝑧 ∣ ∃𝑦(𝜑𝑧 = 𝐴)}
3938, 4eqtri 2161 1 {𝑥 ∣ ∀𝑦(𝜑𝐴𝑥)} = {𝑥 ∣ ∃𝑦(𝜑𝑥 = 𝐴)}
 Colors of variables: wff set class Syntax hints:   → wi 4   ∧ wa 103  ∀wal 1330   = wceq 1332  ∃wex 1469   ∈ wcel 1481  {cab 2126  Vcvv 2689  [wsbc 2912   ⊆ wss 3075  ∩ cint 3778 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-io 699  ax-5 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516  ax-ext 2122 This theorem depends on definitions:  df-bi 116  df-tru 1335  df-nf 1438  df-sb 1737  df-clab 2127  df-cleq 2133  df-clel 2136  df-nfc 2271  df-v 2691  df-sbc 2913  df-in 3081  df-ss 3088  df-int 3779 This theorem is referenced by: (None)
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