Theorem ssres2 4992

Description: Subclass theorem for restriction. (The proof was shortened by Andrew Salmon, 27-Aug-2011.) (Contributed by set.mm contributors, 22-Mar-1998.) (Revised by set.mm contributors, 27-Aug-2011.)

Assertion

Ref	Expression
ssres2	|- (A C_ B -> (C |` A) C_ (C |` B))

Proof of Theorem ssres2

Step	Hyp	Ref	Expression
1		xpss1 4857	. . 3 |- (A C_ B -> (A X. _V) C_ (B X. _V))
2		sslin 3482	. . 3 |- ((A X. _V) C_ (B X. _V) -> (C i^i (A X. _V)) C_ (C i^i (B X. _V)))
3	1, 2	syl 15	. 2 |- (A C_ B -> (C i^i (A X. _V)) C_ (C i^i (B X. _V)))
4		df-res 4789	. 2 |- (C |` A) = (C i^i (A X. _V))
5		df-res 4789	. 2 |- (C |` B) = (C i^i (B X. _V))
6	3, 4, 5	3sstr4g 3313	1 |- (A C_ B -> (C |` A) C_ (C |` B))

Syntax hints:   -> wi 4  _Vcvv 2860   i^i cin 3209   C_ wss 3258   X. cxp 4771   |` cres 4775

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334

This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2479  df-v 2862  df-nin 3212  df-compl 3213  df-in 3214  df-ss 3260  df-opab 4624  df-xp 4785  df-res 4789

This theorem is referenced by:  imass2  5025