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Theorem enqdc1 7505
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 6269 . . . 4 (𝐶 ∈ (N × N) → (1st𝐶) ∈ N)
2 xp2nd 6270 . . . 4 (𝐶 ∈ (N × N) → (2nd𝐶) ∈ N)
31, 2jca 306 . . 3 (𝐶 ∈ (N × N) → ((1st𝐶) ∈ N ∧ (2nd𝐶) ∈ N))
4 enqdc 7504 . . 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 6279 . . . . 5 (𝐶 ∈ (N × N) → 𝐶 = ⟨(1st𝐶), (2nd𝐶)⟩)
76breq2d 4066 . . . 4 (𝐶 ∈ (N × N) → (⟨𝐴, 𝐵⟩ ~Q 𝐶 ↔ ⟨𝐴, 𝐵⟩ ~Q ⟨(1st𝐶), (2nd𝐶)⟩))
87dcbid 840 . . 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
Syntax hints:  wi 4  wa 104  wb 105  DECID wdc 836  wcel 2177  cop 3641   class class class wbr 4054   × cxp 4686  cfv 5285  1st c1st 6242  2nd c2nd 6243  Ncnpi 7415   ~Q ceq 7422
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 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2179  ax-14 2180  ax-ext 2188  ax-coll 4170  ax-sep 4173  ax-nul 4181  ax-pow 4229  ax-pr 4264  ax-un 4493  ax-setind 4598  ax-iinf 4649
This theorem depends on definitions:  df-bi 117  df-dc 837  df-3or 982  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2193  df-cleq 2199  df-clel 2202  df-nfc 2338  df-ne 2378  df-ral 2490  df-rex 2491  df-reu 2492  df-rab 2494  df-v 2775  df-sbc 3003  df-csb 3098  df-dif 3172  df-un 3174  df-in 3176  df-ss 3183  df-nul 3465  df-pw 3623  df-sn 3644  df-pr 3645  df-op 3647  df-uni 3860  df-int 3895  df-iun 3938  df-br 4055  df-opab 4117  df-mpt 4118  df-tr 4154  df-id 4353  df-iord 4426  df-on 4428  df-suc 4431  df-iom 4652  df-xp 4694  df-rel 4695  df-cnv 4696  df-co 4697  df-dm 4698  df-rn 4699  df-res 4700  df-ima 4701  df-iota 5246  df-fun 5287  df-fn 5288  df-f 5289  df-f1 5290  df-fo 5291  df-f1o 5292  df-fv 5293  df-ov 5965  df-oprab 5966  df-mpo 5967  df-1st 6244  df-2nd 6245  df-recs 6409  df-irdg 6474  df-oadd 6524  df-omul 6525  df-ni 7447  df-mi 7449  df-enq 7490
This theorem is referenced by: (None)
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