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Theorem 0pssin 44525
Description: Express that an intersection is not empty. (Contributed by RP, 16-Apr-2020.)
Assertion
Ref Expression
0pssin (∅ ⊊ (𝐴𝐵) ↔ ∃𝑥(𝑥𝐴𝑥𝐵))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem 0pssin
StepHypRef Expression
1 0pss 4366 . 2 (∅ ⊊ (𝐴𝐵) ↔ (𝐴𝐵) ≠ ∅)
2 ndisj 4324 . 2 ((𝐴𝐵) ≠ ∅ ↔ ∃𝑥(𝑥𝐴𝑥𝐵))
31, 2bitri 278 1 (∅ ⊊ (𝐴𝐵) ↔ ∃𝑥(𝑥𝐴𝑥𝐵))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wb 209  wa 400  wex 1808  wcel 2142  wne 2957  cin 3903  wpss 3905  c0 4285
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-ext 2734
This proof depends on definitions:  df-bi 210  df-an 401  df-tru 1572  df-fal 1582  df-ex 1809  df-sb 2096  df-clab 2741  df-cleq 2754  df-clel 2837  df-ne 2958  df-v 3456  df-dif 3907  df-in 3911  df-ss 3921  df-pss 3924  df-nul 4286
This theorem is used by: (None)
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