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

Theorem fco 5107
Description: Composition of two mappings. (Contributed by NM, 29-Aug-1999.) (Proof shortened by Andrew Salmon, 17-Sep-2011.)
Assertion
Ref Expression
fco  |-  ( ( F : B --> C  /\  G : A --> B )  ->  ( F  o.  G ) : A --> C )

Proof of Theorem fco
StepHypRef Expression
1 df-f 4956 . . 3  |-  ( F : B --> C  <->  ( F  Fn  B  /\  ran  F  C_  C ) )
2 df-f 4956 . . 3  |-  ( G : A --> B  <->  ( G  Fn  A  /\  ran  G  C_  B ) )
3 fnco 5058 . . . . . . 7  |-  ( ( F  Fn  B  /\  G  Fn  A  /\  ran  G  C_  B )  ->  ( F  o.  G
)  Fn  A )
433expib 1142 . . . . . 6  |-  ( F  Fn  B  ->  (
( G  Fn  A  /\  ran  G  C_  B
)  ->  ( F  o.  G )  Fn  A
) )
54adantr 270 . . . . 5  |-  ( ( F  Fn  B  /\  ran  F  C_  C )  ->  ( ( G  Fn  A  /\  ran  G  C_  B )  ->  ( F  o.  G )  Fn  A ) )
6 rncoss 4650 . . . . . . 7  |-  ran  ( F  o.  G )  C_ 
ran  F
7 sstr 3016 . . . . . . 7  |-  ( ( ran  ( F  o.  G )  C_  ran  F  /\  ran  F  C_  C )  ->  ran  ( F  o.  G
)  C_  C )
86, 7mpan 415 . . . . . 6  |-  ( ran 
F  C_  C  ->  ran  ( F  o.  G
)  C_  C )
98adantl 271 . . . . 5  |-  ( ( F  Fn  B  /\  ran  F  C_  C )  ->  ran  ( F  o.  G )  C_  C
)
105, 9jctird 310 . . . 4  |-  ( ( F  Fn  B  /\  ran  F  C_  C )  ->  ( ( G  Fn  A  /\  ran  G  C_  B )  ->  (
( F  o.  G
)  Fn  A  /\  ran  ( F  o.  G
)  C_  C )
) )
1110imp 122 . . 3  |-  ( ( ( F  Fn  B  /\  ran  F  C_  C
)  /\  ( G  Fn  A  /\  ran  G  C_  B ) )  -> 
( ( F  o.  G )  Fn  A  /\  ran  ( F  o.  G )  C_  C
) )
121, 2, 11syl2anb 285 . 2  |-  ( ( F : B --> C  /\  G : A --> B )  ->  ( ( F  o.  G )  Fn  A  /\  ran  ( F  o.  G )  C_  C ) )
13 df-f 4956 . 2  |-  ( ( F  o.  G ) : A --> C  <->  ( ( F  o.  G )  Fn  A  /\  ran  ( F  o.  G )  C_  C ) )
1412, 13sylibr 132 1  |-  ( ( F : B --> C  /\  G : A --> B )  ->  ( F  o.  G ) : A --> C )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 102    C_ wss 2982   ran crn 4392    o. ccom 4395    Fn wfn 4947   -->wf 4948
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 663  ax-5 1377  ax-7 1378  ax-gen 1379  ax-ie1 1423  ax-ie2 1424  ax-8 1436  ax-10 1437  ax-11 1438  ax-i12 1439  ax-bndl 1440  ax-4 1441  ax-14 1446  ax-17 1460  ax-i9 1464  ax-ial 1468  ax-i5r 1469  ax-ext 2065  ax-sep 3916  ax-pow 3968  ax-pr 3992
This theorem depends on definitions:  df-bi 115  df-3an 922  df-tru 1288  df-nf 1391  df-sb 1688  df-eu 1946  df-mo 1947  df-clab 2070  df-cleq 2076  df-clel 2079  df-nfc 2212  df-ral 2358  df-rex 2359  df-v 2612  df-un 2986  df-in 2988  df-ss 2995  df-pw 3402  df-sn 3422  df-pr 3423  df-op 3425  df-br 3806  df-opab 3860  df-id 4076  df-xp 4397  df-rel 4398  df-cnv 4399  df-co 4400  df-dm 4401  df-rn 4402  df-fun 4954  df-fn 4955  df-f 4956
This theorem is referenced by:  fco2  5108  f1co  5153  foco  5168  ialgcvg  10655
  Copyright terms: Public domain W3C validator