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Theorem enqdc1 7424
Description: The equivalence relation for positive fractions is decidable. (Contributed by Jim Kingdon, 7-Sep-2019.)
Assertion
Ref Expression
enqdc1  |-  ( ( ( A  e.  N.  /\  B  e.  N. )  /\  C  e.  ( N.  X.  N. ) )  -> DECID  <. A ,  B >.  ~Q  C )

Proof of Theorem enqdc1
StepHypRef Expression
1 xp1st 6220 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( 1st `  C )  e.  N. )
2 xp2nd 6221 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( 2nd `  C )  e.  N. )
31, 2jca 306 . . 3  |-  ( C  e.  ( N.  X.  N. )  ->  ( ( 1st `  C )  e.  N.  /\  ( 2nd `  C )  e. 
N. ) )
4 enqdc 7423 . . 3  |-  ( ( ( A  e.  N.  /\  B  e.  N. )  /\  ( ( 1st `  C
)  e.  N.  /\  ( 2nd `  C )  e.  N. ) )  -> DECID  <. A ,  B >.  ~Q 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
53, 4sylan2 286 . 2  |-  ( ( ( A  e.  N.  /\  B  e.  N. )  /\  C  e.  ( N.  X.  N. ) )  -> DECID  <. A ,  B >.  ~Q 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
6 1st2nd2 6230 . . . . 5  |-  ( C  e.  ( N.  X.  N. )  ->  C  = 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
76breq2d 4042 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( <. A ,  B >.  ~Q  C  <->  <. A ,  B >.  ~Q  <. ( 1st `  C
) ,  ( 2nd `  C ) >. )
)
87dcbid 839 . . 3  |-  ( C  e.  ( N.  X.  N. )  ->  (DECID  <. A ,  B >.  ~Q  C  <-> DECID  <. A ,  B >.  ~Q  <. ( 1st `  C
) ,  ( 2nd `  C ) >. )
)
98adantl 277 . 2  |-  ( ( ( A  e.  N.  /\  B  e.  N. )  /\  C  e.  ( N.  X.  N. ) )  ->  (DECID 
<. A ,  B >.  ~Q  C  <-> DECID  <. A ,  B >.  ~Q 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
)
105, 9mpbird 167 1  |-  ( ( ( A  e.  N.  /\  B  e.  N. )  /\  C  e.  ( N.  X.  N. ) )  -> DECID  <. A ,  B >.  ~Q  C )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105  DECID wdc 835    e. wcel 2164   <.cop 3622   class class class wbr 4030    X. cxp 4658   ` cfv 5255   1stc1st 6193   2ndc2nd 6194   N.cnpi 7334    ~Q ceq 7341
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-in1 615  ax-in2 616  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-13 2166  ax-14 2167  ax-ext 2175  ax-coll 4145  ax-sep 4148  ax-nul 4156  ax-pow 4204  ax-pr 4239  ax-un 4465  ax-setind 4570  ax-iinf 4621
This theorem depends on definitions:  df-bi 117  df-dc 836  df-3or 981  df-3an 982  df-tru 1367  df-fal 1370  df-nf 1472  df-sb 1774  df-eu 2045  df-mo 2046  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-ne 2365  df-ral 2477  df-rex 2478  df-reu 2479  df-rab 2481  df-v 2762  df-sbc 2987  df-csb 3082  df-dif 3156  df-un 3158  df-in 3160  df-ss 3167  df-nul 3448  df-pw 3604  df-sn 3625  df-pr 3626  df-op 3628  df-uni 3837  df-int 3872  df-iun 3915  df-br 4031  df-opab 4092  df-mpt 4093  df-tr 4129  df-id 4325  df-iord 4398  df-on 4400  df-suc 4403  df-iom 4624  df-xp 4666  df-rel 4667  df-cnv 4668  df-co 4669  df-dm 4670  df-rn 4671  df-res 4672  df-ima 4673  df-iota 5216  df-fun 5257  df-fn 5258  df-f 5259  df-f1 5260  df-fo 5261  df-f1o 5262  df-fv 5263  df-ov 5922  df-oprab 5923  df-mpo 5924  df-1st 6195  df-2nd 6196  df-recs 6360  df-irdg 6425  df-oadd 6475  df-omul 6476  df-ni 7366  df-mi 7368  df-enq 7409
This theorem is referenced by: (None)
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