Theorem resiima 5120

Description: The image of a restriction of the identity function. (Contributed by FL, 31-Dec-2006.)

Assertion

Ref	Expression
resiima	|- ( B C_ A -> ( ( _I |` A ) " B ) = B )

Proof of Theorem resiima

Step	Hyp	Ref	Expression
1		df-ima 4762	. . 3 |- ( ( _I |` A ) " B ) = ran ( ( _I |` A ) |` B )
2	1	a1i 9	. 2 |- ( B C_ A -> ( ( _I |` A ) " B ) = ran ( ( _I |` A ) |` B ) )
3		resabs1 5067	. . 3 |- ( B C_ A -> ( ( _I |` A ) |` B ) = ( _I |` B ) )
4	3	rneqd 4986	. 2 |- ( B C_ A -> ran ( ( _I |` A ) |` B ) = ran ( _I |` B ) )
5		rnresi 5119	. . 3 |- ran ( _I |` B ) = B
6	5	a1i 9	. 2 |- ( B C_ A -> ran ( _I |` B ) = B )
7	2, 4, 6	3eqtrd 2269	1 |- ( B C_ A -> ( ( _I |` A ) " B ) = B )

Syntax hints:   -> wi 4   = wceq 1398   C_ wss 3211   _I cid 4409   ran crn 4750   |` cres 4751   "cima 4752

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 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-14 2206  ax-ext 2214  ax-sep 4228  ax-pow 4287  ax-pr 4322

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-eu 2083  df-mo 2084  df-clab 2219  df-cleq 2225  df-clel 2228  df-nfc 2373  df-ral 2525  df-rex 2526  df-v 2815  df-un 3215  df-in 3217  df-ss 3224  df-pw 3671  df-sn 3695  df-pr 3696  df-op 3698  df-br 4110  df-opab 4172  df-id 4414  df-xp 4755  df-rel 4756  df-cnv 4757  df-dm 4759  df-rn 4760  df-res 4761  df-ima 4762

This theorem is referenced by:  ssidcn  15075