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Theorem intmin3 3642
Description: Under subset ordering, the intersection of a class abstraction is less than or equal to any of its members. (Contributed by NM, 3-Jul-2005.)
Hypotheses
Ref Expression
intmin3.2 (𝑥 = 𝐴 → (𝜑𝜓))
intmin3.3 𝜓
Assertion
Ref Expression
intmin3 (𝐴𝑉 {𝑥𝜑} ⊆ 𝐴)
Distinct variable groups:   𝑥,𝐴   𝜓,𝑥
Allowed substitution hints:   𝜑(𝑥)   𝑉(𝑥)

Proof of Theorem intmin3
StepHypRef Expression
1 intmin3.3 . . 3 𝜓
2 intmin3.2 . . . 4 (𝑥 = 𝐴 → (𝜑𝜓))
32elabg 2688 . . 3 (𝐴𝑉 → (𝐴 ∈ {𝑥𝜑} ↔ 𝜓))
41, 3mpbiri 157 . 2 (𝐴𝑉𝐴 ∈ {𝑥𝜑})
5 intss1 3630 . 2 (𝐴 ∈ {𝑥𝜑} → {𝑥𝜑} ⊆ 𝐴)
64, 5syl 14 1 (𝐴𝑉 {𝑥𝜑} ⊆ 𝐴)
Colors of variables: wff set class
Syntax hints:  wi 4  wb 98   = wceq 1243  wcel 1393  {cab 2026  wss 2917   cint 3615
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-io 630  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-10 1396  ax-11 1397  ax-i12 1398  ax-bndl 1399  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022
This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-nfc 2167  df-v 2559  df-in 2924  df-ss 2931  df-int 3616
This theorem is referenced by:  intid  3960
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