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Theorem inelcm 3498
Description: The intersection of classes with a common member is nonempty. (Contributed by NM, 7-Apr-1994.)
Assertion
Ref Expression
inelcm  |-  ( ( A  e.  B  /\  A  e.  C )  ->  ( B  i^i  C
)  =/=  (/) )

Proof of Theorem inelcm
StepHypRef Expression
1 elin 3333 . 2  |-  ( A  e.  ( B  i^i  C )  <->  ( A  e.  B  /\  A  e.  C ) )
2 ne0i 3444 . 2  |-  ( A  e.  ( B  i^i  C )  ->  ( B  i^i  C )  =/=  (/) )
31, 2sylbir 135 1  |-  ( ( A  e.  B  /\  A  e.  C )  ->  ( B  i^i  C
)  =/=  (/) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    e. wcel 2160    =/= wne 2360    i^i cin 3143   (/)c0 3437
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2171
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2176  df-cleq 2182  df-clel 2185  df-nfc 2321  df-ne 2361  df-v 2754  df-dif 3146  df-in 3150  df-nul 3438
This theorem is referenced by:  minel  3499  disjiun  4013
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