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Theorem enqdc1 7729
Description: The equivalence relation for positive fractions is decidable. (Contributed by Jim Kingdon, 7-Sep-2019.)
Assertion
Ref Expression
enqdc1 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → DECID𝐴, 𝐵⟩ ~Q 𝐶)

Proof of Theorem enqdc1
StepHypRef Expression
1 xp1st 6399 . . . 4 (𝐶 ∈ (N × N) → (1st𝐶) ∈ N)
2 xp2nd 6400 . . . 4 (𝐶 ∈ (N × N) → (2nd𝐶) ∈ N)
31, 2jca 306 . . 3 (𝐶 ∈ (N × N) → ((1st𝐶) ∈ N ∧ (2nd𝐶) ∈ N))
4 enqdc 7728 . . 3 (((𝐴N𝐵N) ∧ ((1st𝐶) ∈ N ∧ (2nd𝐶) ∈ N)) → DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩)
53, 4sylan2 286 . 2 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩)
6 1st2nd2 6409 . . . . 5 (𝐶 ∈ (N × N) → 𝐶 = ⟨(1st𝐶), (2nd𝐶)⟩)
76breq2d 4142 . . . 4 (𝐶 ∈ (N × N) → (⟨𝐴, 𝐵⟩ ~Q 𝐶 ↔ ⟨𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
87dcbid 850 . . 3 (𝐶 ∈ (N × N) → (DECID𝐴, 𝐵⟩ ~Q 𝐶DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
98adantl 277 . 2 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → (DECID𝐴, 𝐵⟩ ~Q 𝐶DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
105, 9mpbird 167 1 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → DECID𝐴, 𝐵⟩ ~Q 𝐶)
Colors of variables:    wff set class
This proof depends on syntax axioms:  wi 4  wa 104  wb 105  DECID wdc 846  wcel 2209  cop 3712   class class class wbr 4130   × cxp 4772  cfv 5377  1st c1st 6372  2nd c2nd 6373  Ncnpi 7639   ~Q ceq 7646
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 4246  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-iinf 4735
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 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-iord 4511  df-on 4513  df-suc 4516  df-iom 4738  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-ov 6088  df-oprab 6089  df-mpo 6090  df-1st 6374  df-2nd 6375  df-recs 6576  df-irdg 6641  df-oadd 6691  df-omul 6692  df-ni 7671  df-mi 7673  df-enq 7714
This theorem is used by: (None)
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