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Theorem inelcm 3521
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 3356 . 2  |-  ( A  e.  ( B  i^i  C )  <->  ( A  e.  B  /\  A  e.  C ) )
2 ne0i 3467 . 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 2176    =/= wne 2376    i^i cin 3165   (/)c0 3460
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 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187
This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ne 2377  df-v 2774  df-dif 3168  df-in 3172  df-nul 3461
This theorem is referenced by:  minel  3522  disjiun  4040
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