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Theorem enqdc1 7736
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 6403 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( 1st `  C )  e.  N. )
2 xp2nd 6404 . . . 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 7735 . . 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 6413 . . . . 5  |-  ( C  e.  ( N.  X.  N. )  ->  C  = 
<. ( 1st `  C
) ,  ( 2nd `  C ) >. )
76breq2d 4143 . . . 4  |-  ( C  e.  ( N.  X.  N. )  ->  ( <. A ,  B >.  ~Q  C  <->  <. A ,  B >.  ~Q  <. ( 1st `  C
) ,  ( 2nd `  C ) >. )
)
87dcbid 850 . . 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
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    <-> wb 105  DECID wdc 846    e. wcel 2209   <.cop 3712   class class class wbr 4131    X. cxp 4774   ` cfv 5380   1stc1st 6376   2ndc2nd 6377   N.cnpi 7646    ~Q ceq 7653
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4248  ax-sep 4251  ax-nul 4261  ax-pow 4313  ax-pr 4348  ax-un 4580  ax-setind 4686  ax-iinf 4737
This proof depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-reu 2535  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4132  df-opab 4194  df-mpt 4195  df-tr 4232  df-id 4440  df-iord 4513  df-on 4515  df-suc 4518  df-iom 4740  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fo 5386  df-f1o 5387  df-fv 5388  df-ov 6091  df-oprab 6092  df-mpo 6093  df-1st 6378  df-2nd 6379  df-recs 6580  df-irdg 6645  df-oadd 6695  df-omul 6696  df-ni 7678  df-mi 7680  df-enq 7721
This theorem is used by: (None)
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