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

Theorem ssind 3397
Description: A deduction showing that a subclass of two classes is a subclass of their intersection. (Contributed by Jonathan Ben-Naim, 3-Jun-2011.)
Hypotheses
Ref Expression
ssind.1  |-  ( ph  ->  A  C_  B )
ssind.2  |-  ( ph  ->  A  C_  C )
Assertion
Ref Expression
ssind  |-  ( ph  ->  A  C_  ( B  i^i  C ) )

Proof of Theorem ssind
StepHypRef Expression
1 ssind.1 . 2  |-  ( ph  ->  A  C_  B )
2 ssind.2 . 2  |-  ( ph  ->  A  C_  C )
3 ssin 3395 . . 3  |-  ( ( A  C_  B  /\  A  C_  C )  <->  A  C_  ( B  i^i  C ) )
43biimpi 120 . 2  |-  ( ( A  C_  B  /\  A  C_  C )  ->  A  C_  ( B  i^i  C ) )
51, 2, 4syl2anc 411 1  |-  ( ph  ->  A  C_  ( B  i^i  C ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    i^i cin 3165    C_ wss 3166
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-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-v 2774  df-in 3172  df-ss 3179
This theorem is referenced by:  ntrin  14596  lmss  14718
  Copyright terms: Public domain W3C validator