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Theorem nnmcan 3190
Description: Cancellation law for multiplication of natural numbers.
Assertion
Ref Expression
nnmcan (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → ((A ·o B) = (A ·o C) ↔ B = C))

Proof of Theorem nnmcan
StepHypRef Expression
1 nnmordi 3188 . . . . . . . . . 10 ((B ∈ ω ∧ C ∈ ω ∧ A ∈ ω) → ((BC ∧ ∅ ∈ A) → (A ·o B) ∈ (A ·o C)))
213comr 618 . . . . . . . . 9 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → ((BC ∧ ∅ ∈ A) → (A ·o B) ∈ (A ·o C)))
3 nnmordi 3188 . . . . . . . . . 10 ((C ∈ ω ∧ B ∈ ω ∧ A ∈ ω) → ((CB ∧ ∅ ∈ A) → (A ·o C) ∈ (A ·o B)))
433com13 615 . . . . . . . . 9 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → ((CB ∧ ∅ ∈ A) → (A ·o C) ∈ (A ·o B)))
52, 4orim12d 436 . . . . . . . 8 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → (((BC ∧ ∅ ∈ A) ∨ (CB ∧ ∅ ∈ A)) → ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
6 andir 457 . . . . . . . 8 (((BCCB) ∧ ∅ ∈ A) ↔ ((BC ∧ ∅ ∈ A) ∨ (CB ∧ ∅ ∈ A)))
75, 6syl5ib 181 . . . . . . 7 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → (((BCCB) ∧ ∅ ∈ A) → ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
87exp3a 292 . . . . . 6 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → ((BCCB) → (∅ ∈ A → ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B)))))
98com23 32 . . . . 5 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → (∅ ∈ A → ((BCCB) → ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B)))))
109imp 277 . . . 4 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → ((BCCB) → ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
1110con3d 87 . . 3 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → (¬ ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B)) → ¬ (BCCB)))
12 ordtri3 2234 . . . . . 6 ((Ord (A ·o B) ∧ Ord (A ·o C)) → ((A ·o B) = (A ·o C) ↔ ¬ ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
13 nnmcl 3173 . . . . . . 7 ((A ∈ ω ∧ B ∈ ω) → (A ·o B) ∈ ω)
14 nnord 2381 . . . . . . 7 ((A ·o B) ∈ ω → Ord (A ·o B))
1513, 14syl 12 . . . . . 6 ((A ∈ ω ∧ B ∈ ω) → Ord (A ·o B))
16 nnmcl 3173 . . . . . . 7 ((A ∈ ω ∧ C ∈ ω) → (A ·o C) ∈ ω)
17 nnord 2381 . . . . . . 7 ((A ·o C) ∈ ω → Ord (A ·o C))
1816, 17syl 12 . . . . . 6 ((A ∈ ω ∧ C ∈ ω) → Ord (A ·o C))
1912, 15, 18syl2an 349 . . . . 5 (((A ∈ ω ∧ B ∈ ω) ∧ (A ∈ ω ∧ C ∈ ω)) → ((A ·o B) = (A ·o C) ↔ ¬ ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
20193impdi 630 . . . 4 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → ((A ·o B) = (A ·o C) ↔ ¬ ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
2120adantr 306 . . 3 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → ((A ·o B) = (A ·o C) ↔ ¬ ((A ·o B) ∈ (A ·o C) ∨ (A ·o C) ∈ (A ·o B))))
22 ordtri3 2234 . . . . . 6 ((Ord B ∧ Ord C) → (B = C ↔ ¬ (BCCB)))
23 nnord 2381 . . . . . 6 (B ∈ ω → Ord B)
24 nnord 2381 . . . . . 6 (C ∈ ω → Ord C)
2522, 23, 24syl2an 349 . . . . 5 ((B ∈ ω ∧ C ∈ ω) → (B = C ↔ ¬ (BCCB)))
26253adant1 597 . . . 4 ((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) → (B = C ↔ ¬ (BCCB)))
2726adantr 306 . . 3 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → (B = C ↔ ¬ (BCCB)))
2811, 21, 273imtr4d 421 . 2 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → ((A ·o B) = (A ·o C) → B = C))
29 opreq2 3007 . . 3 (B = C → (A ·o B) = (A ·o C))
3029a1i 7 . 2 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → (B = C → (A ·o B) = (A ·o C)))
3128, 30impbid 397 1 (((A ∈ ω ∧ B ∈ ω ∧ C ∈ ω) ∧ ∅ ∈ A) → ((A ·o B) = (A ·o C) ↔ B = C))
Colors of variables: wff set class
Syntax hints:  ¬ wn 1   → wi 2   ↔ wb 127   ∨ wo 195   ∧ wa 196   ∧ w3a 581   = wceq 1091   ∈ wcel 1092  ∅c0 1707  Ord word 2198  ωcom 2372  (class class class)co 3001   ·o comu 3102
This theorem is referenced by:  mulcanpi 3821
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3or 582  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-ral 1205  df-rex 1206  df-rab 1208  df-v 1349  df-sbc 1441  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-if 1777  df-pw 1799  df-sn 1811  df-pr 1812  df-tp 1814  df-op 1815  df-uni 1920  df-iun 1996  df-tr 2042  df-br 2063  df-opab 2098  df-eprel 2122  df-id 2125  df-po 2128  df-so 2138  df-fr 2169  df-we 2186  df-ord 2202  df-on 2203  df-lim 2204  df-suc 2205  df-om 2373  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fn 2433  df-fv 2438  df-rdg 2970  df-opr 3003  df-oprab 3004  df-oadd 3106  df-omul 3107
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