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Theorem enqdc1 7422
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 6218 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( 1st `  C )  e.  N. )
2 xp2nd 6219 . . . 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 7421 . . 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 6228 . . . . 5  |-  ( C  e.  ( N.  X.  N. )  ->  C  = 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
76breq2d 4041 . . . 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 3621   class class class wbr 4029    X. cxp 4657   ` cfv 5254   1stc1st 6191   2ndc2nd 6192   N.cnpi 7332    ~Q ceq 7339
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 4144  ax-sep 4147  ax-nul 4155  ax-pow 4203  ax-pr 4238  ax-un 4464  ax-setind 4569  ax-iinf 4620
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 2986  df-csb 3081  df-dif 3155  df-un 3157  df-in 3159  df-ss 3166  df-nul 3447  df-pw 3603  df-sn 3624  df-pr 3625  df-op 3627  df-uni 3836  df-int 3871  df-iun 3914  df-br 4030  df-opab 4091  df-mpt 4092  df-tr 4128  df-id 4324  df-iord 4397  df-on 4399  df-suc 4402  df-iom 4623  df-xp 4665  df-rel 4666  df-cnv 4667  df-co 4668  df-dm 4669  df-rn 4670  df-res 4671  df-ima 4672  df-iota 5215  df-fun 5256  df-fn 5257  df-f 5258  df-f1 5259  df-fo 5260  df-f1o 5261  df-fv 5262  df-ov 5921  df-oprab 5922  df-mpo 5923  df-1st 6193  df-2nd 6194  df-recs 6358  df-irdg 6423  df-oadd 6473  df-omul 6474  df-ni 7364  df-mi 7366  df-enq 7407
This theorem is referenced by: (None)
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