Theorem fco2 5354

Description: Functionality of a composition with weakened out of domain condition on the first argument. (Contributed by Stefan O'Rear, 11-Mar-2015.)

Assertion

Ref	Expression
fco2	|- ( ( ( F |` B ) : B --> C /\ G : A --> B ) -> ( F o. G ) : A --> C )

Proof of Theorem fco2

Step	Hyp	Ref	Expression
1		fco 5353	. 2 |- ( ( ( F |` B ) : B --> C /\ G : A --> B ) -> ( ( F |` B ) o. G ) : A --> C )
2		frn 5346	. . . . 5 |- ( G : A --> B -> ran G C_ B )
3		cores 5107	. . . . 5 |- ( ran G C_ B -> ( ( F |` B ) o. G ) = ( F o. G ) )
4	2, 3	syl 14	. . . 4 |- ( G : A --> B -> ( ( F |` B ) o. G ) = ( F o. G ) )
5	4	adantl 275	. . 3 |- ( ( ( F |` B ) : B --> C /\ G : A --> B ) -> ( ( F |` B ) o. G ) = ( F o. G ) )
6	5	feq1d 5324	. 2 |- ( ( ( F |` B ) : B --> C /\ G : A --> B ) -> ( ( ( F |` B ) o. G ) : A --> C <-> ( F o. G ) : A --> C ) )
7	1, 6	mpbid 146	1 |- ( ( ( F |` B ) : B --> C /\ G : A --> B ) -> ( F o. G ) : A --> C )

Syntax hints:   -> wi 4   /\ wa 103   = wceq 1343   C_ wss 3116   ran crn 4605   |` cres 4606   o. ccom 4608   -->wf 5184

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-14 2139  ax-ext 2147  ax-sep 4100  ax-pow 4153  ax-pr 4187

This theorem depends on definitions:  df-bi 116  df-3an 970  df-tru 1346  df-nf 1449  df-sb 1751  df-eu 2017  df-mo 2018  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-ral 2449  df-rex 2450  df-v 2728  df-un 3120  df-in 3122  df-ss 3129  df-pw 3561  df-sn 3582  df-pr 3583  df-op 3585  df-br 3983  df-opab 4044  df-id 4271  df-xp 4610  df-rel 4611  df-cnv 4612  df-co 4613  df-dm 4614  df-rn 4615  df-res 4616  df-fun 5190  df-fn 5191  df-f 5192

This theorem is referenced by:  isomninnlem  13909  iswomninnlem  13928  ismkvnnlem  13931