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Theorem enqdc1 7018
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 5974 . . . 4 (𝐶 ∈ (N × N) → (1st𝐶) ∈ N)
2 xp2nd 5975 . . . 4 (𝐶 ∈ (N × N) → (2nd𝐶) ∈ N)
31, 2jca 301 . . 3 (𝐶 ∈ (N × N) → ((1st𝐶) ∈ N ∧ (2nd𝐶) ∈ N))
4 enqdc 7017 . . 3 (((𝐴N𝐵N) ∧ ((1st𝐶) ∈ N ∧ (2nd𝐶) ∈ N)) → DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩)
53, 4sylan2 281 . 2 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩)
6 1st2nd2 5983 . . . . 5 (𝐶 ∈ (N × N) → 𝐶 = ⟨(1st𝐶), (2nd𝐶)⟩)
76breq2d 3879 . . . 4 (𝐶 ∈ (N × N) → (⟨𝐴, 𝐵⟩ ~Q 𝐶 ↔ ⟨𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
87dcbid 789 . . 3 (𝐶 ∈ (N × N) → (DECID𝐴, 𝐵⟩ ~Q 𝐶DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
98adantl 272 . 2 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → (DECID𝐴, 𝐵⟩ ~Q 𝐶DECID𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
105, 9mpbird 166 1 (((𝐴N𝐵N) ∧ 𝐶 ∈ (N × N)) → DECID𝐴, 𝐵⟩ ~Q 𝐶)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  wb 104  DECID wdc 783  wcel 1445  cop 3469   class class class wbr 3867   × cxp 4465  cfv 5049  1st c1st 5947  2nd c2nd 5948  Ncnpi 6928   ~Q ceq 6935
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 582  ax-in2 583  ax-io 668  ax-5 1388  ax-7 1389  ax-gen 1390  ax-ie1 1434  ax-ie2 1435  ax-8 1447  ax-10 1448  ax-11 1449  ax-i12 1450  ax-bndl 1451  ax-4 1452  ax-13 1456  ax-14 1457  ax-17 1471  ax-i9 1475  ax-ial 1479  ax-i5r 1480  ax-ext 2077  ax-coll 3975  ax-sep 3978  ax-nul 3986  ax-pow 4030  ax-pr 4060  ax-un 4284  ax-setind 4381  ax-iinf 4431
This theorem depends on definitions:  df-bi 116  df-dc 784  df-3or 928  df-3an 929  df-tru 1299  df-fal 1302  df-nf 1402  df-sb 1700  df-eu 1958  df-mo 1959  df-clab 2082  df-cleq 2088  df-clel 2091  df-nfc 2224  df-ne 2263  df-ral 2375  df-rex 2376  df-reu 2377  df-rab 2379  df-v 2635  df-sbc 2855  df-csb 2948  df-dif 3015  df-un 3017  df-in 3019  df-ss 3026  df-nul 3303  df-pw 3451  df-sn 3472  df-pr 3473  df-op 3475  df-uni 3676  df-int 3711  df-iun 3754  df-br 3868  df-opab 3922  df-mpt 3923  df-tr 3959  df-id 4144  df-iord 4217  df-on 4219  df-suc 4222  df-iom 4434  df-xp 4473  df-rel 4474  df-cnv 4475  df-co 4476  df-dm 4477  df-rn 4478  df-res 4479  df-ima 4480  df-iota 5014  df-fun 5051  df-fn 5052  df-f 5053  df-f1 5054  df-fo 5055  df-f1o 5056  df-fv 5057  df-ov 5693  df-oprab 5694  df-mpt2 5695  df-1st 5949  df-2nd 5950  df-recs 6108  df-irdg 6173  df-oadd 6223  df-omul 6224  df-ni 6960  df-mi 6962  df-enq 7003
This theorem is referenced by: (None)
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