Theorem ssind 3346

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

Step	Hyp	Ref	Expression
1		ssind.1	. 2 |- ( ph -> A C_ B )
2		ssind.2	. 2 |- ( ph -> A C_ C )
3		ssin 3344	. . 3 |- ( ( A C_ B /\ A C_ C ) <-> A C_ ( B i^i C ) )
4	3	biimpi 119	. 2 |- ( ( A C_ B /\ A C_ C ) -> A C_ ( B i^i C ) )
5	1, 2, 4	syl2anc 409	1 |- ( ph -> A C_ ( B i^i C ) )

Syntax hints:   -> wi 4   /\ wa 103   i^i cin 3115   C_ wss 3116

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-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-v 2728  df-in 3122  df-ss 3129

This theorem is referenced by:  ntrin  12764  lmss  12886