ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  inelcm Unicode version

Theorem inelcm 3418
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 3254 . 2  |-  ( A  e.  ( B  i^i  C )  <->  ( A  e.  B  /\  A  e.  C ) )
2 ne0i 3364 . 2  |-  ( A  e.  ( B  i^i  C )  ->  ( B  i^i  C )  =/=  (/) )
31, 2sylbir 134 1  |-  ( ( A  e.  B  /\  A  e.  C )  ->  ( B  i^i  C
)  =/=  (/) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 103    e. wcel 1480    =/= wne 2306    i^i cin 3065   (/)c0 3358
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-in1 603  ax-in2 604  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2119
This theorem depends on definitions:  df-bi 116  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-ne 2307  df-v 2683  df-dif 3068  df-in 3072  df-nul 3359
This theorem is referenced by:  minel  3419  disjiun  3919
  Copyright terms: Public domain W3C validator