MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  f1stres Structured version   Unicode version

Theorem f1stres 6360
Description: Mapping of a restriction of the  1st (first member of an ordered pair) function. (Contributed by NM, 11-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.)
Assertion
Ref Expression
f1stres  |-  ( 1st  |`  ( A  X.  B
) ) : ( A  X.  B ) --> A

Proof of Theorem f1stres
Dummy variables  x  y  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 vex 2951 . . . . . . . 8  |-  y  e. 
_V
2 vex 2951 . . . . . . . 8  |-  z  e. 
_V
31, 2op1sta 5343 . . . . . . 7  |-  U. dom  {
<. y ,  z >. }  =  y
43eleq1i 2498 . . . . . 6  |-  ( U. dom  { <. y ,  z
>. }  e.  A  <->  y  e.  A )
54biimpri 198 . . . . 5  |-  ( y  e.  A  ->  U. dom  {
<. y ,  z >. }  e.  A )
65adantr 452 . . . 4  |-  ( ( y  e.  A  /\  z  e.  B )  ->  U. dom  { <. y ,  z >. }  e.  A )
76rgen2 2794 . . 3  |-  A. y  e.  A  A. z  e.  B  U. dom  { <. y ,  z >. }  e.  A
8 sneq 3817 . . . . . . 7  |-  ( x  =  <. y ,  z
>.  ->  { x }  =  { <. y ,  z
>. } )
98dmeqd 5064 . . . . . 6  |-  ( x  =  <. y ,  z
>.  ->  dom  { x }  =  dom  { <. y ,  z >. } )
109unieqd 4018 . . . . 5  |-  ( x  =  <. y ,  z
>.  ->  U. dom  { x }  =  U. dom  { <. y ,  z >. } )
1110eleq1d 2501 . . . 4  |-  ( x  =  <. y ,  z
>.  ->  ( U. dom  { x }  e.  A  <->  U.
dom  { <. y ,  z
>. }  e.  A ) )
1211ralxp 5008 . . 3  |-  ( A. x  e.  ( A  X.  B ) U. dom  { x }  e.  A  <->  A. y  e.  A  A. z  e.  B  U. dom  { <. y ,  z
>. }  e.  A )
137, 12mpbir 201 . 2  |-  A. x  e.  ( A  X.  B
) U. dom  {
x }  e.  A
14 df-1st 6341 . . . . 5  |-  1st  =  ( x  e.  _V  |->  U.
dom  { x } )
1514reseq1i 5134 . . . 4  |-  ( 1st  |`  ( A  X.  B
) )  =  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )
16 ssv 3360 . . . . 5  |-  ( A  X.  B )  C_  _V
17 resmpt 5183 . . . . 5  |-  ( ( A  X.  B ) 
C_  _V  ->  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } ) )
1816, 17ax-mp 8 . . . 4  |-  ( ( x  e.  _V  |->  U.
dom  { x } )  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } )
1915, 18eqtri 2455 . . 3  |-  ( 1st  |`  ( A  X.  B
) )  =  ( x  e.  ( A  X.  B )  |->  U.
dom  { x } )
2019fmpt 5882 . 2  |-  ( A. x  e.  ( A  X.  B ) U. dom  { x }  e.  A  <->  ( 1st  |`  ( A  X.  B ) ) : ( A  X.  B
) --> A )
2113, 20mpbi 200 1  |-  ( 1st  |`  ( A  X.  B
) ) : ( A  X.  B ) --> A
Colors of variables: wff set class
Syntax hints:    = wceq 1652    e. wcel 1725   A.wral 2697   _Vcvv 2948    C_ wss 3312   {csn 3806   <.cop 3809   U.cuni 4007    e. cmpt 4258    X. cxp 4868   dom cdm 4870    |` cres 4872   -->wf 5442   1stc1st 6339
This theorem is referenced by:  fo1stres  6362  1stcof  6366  fparlem1  6438  domssex2  7259  domssex  7260  unxpwdom2  7548  1stfcl  14286  tx1cn  17633  xpinpreima  24296  xpinpreima2  24297  1stmbfm  24602  hausgraph  27499
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1555  ax-5 1566  ax-17 1626  ax-9 1666  ax-8 1687  ax-14 1729  ax-6 1744  ax-7 1749  ax-11 1761  ax-12 1950  ax-ext 2416  ax-sep 4322  ax-nul 4330  ax-pr 4395
This theorem depends on definitions:  df-bi 178  df-or 360  df-an 361  df-3an 938  df-tru 1328  df-ex 1551  df-nf 1554  df-sb 1659  df-eu 2284  df-mo 2285  df-clab 2422  df-cleq 2428  df-clel 2431  df-nfc 2560  df-ne 2600  df-ral 2702  df-rex 2703  df-rab 2706  df-v 2950  df-sbc 3154  df-csb 3244  df-dif 3315  df-un 3317  df-in 3319  df-ss 3326  df-nul 3621  df-if 3732  df-sn 3812  df-pr 3813  df-op 3815  df-uni 4008  df-iun 4087  df-br 4205  df-opab 4259  df-mpt 4260  df-id 4490  df-xp 4876  df-rel 4877  df-cnv 4878  df-co 4879  df-dm 4880  df-rn 4881  df-res 4882  df-ima 4883  df-iota 5410  df-fun 5448  df-fn 5449  df-f 5450  df-fv 5454  df-1st 6341
  Copyright terms: Public domain W3C validator