Theorem omord 8503

Description: Ordering property of ordinal multiplication. Proposition 8.19 of [TakeutiZaring] p. 63. Theorem 3.16 of [Schloeder] p. 9. (Contributed by NM, 14-Dec-2004.)

Assertion

Ref	Expression
omord	⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐴 ∈ 𝐵 ∧ ∅ ∈ 𝐶) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))

Proof of Theorem omord

Step	Hyp	Ref	Expression
1		omord2 8502	. . . 4 ⊢ (((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈ 𝐶) → (𝐴 ∈ 𝐵 ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))
2	1	ex 412	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → (∅ ∈ 𝐶 → (𝐴 ∈ 𝐵 ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))))
3	2	pm5.32rd 578	. 2 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐴 ∈ 𝐵 ∧ ∅ ∈ 𝐶) ↔ ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) ∧ ∅ ∈ 𝐶)))
4		simpl 482	. . 3 ⊢ (((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) ∧ ∅ ∈ 𝐶) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))
5		ne0i 4281	. . . . . . . 8 ⊢ ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → (𝐶 ·o 𝐵) ≠ ∅)
6		om0r 8474	. . . . . . . . . 10 ⊢ (𝐵 ∈ On → (∅ ·o 𝐵) = ∅)
7		oveq1 7374	. . . . . . . . . . 11 ⊢ (𝐶 = ∅ → (𝐶 ·o 𝐵) = (∅ ·o 𝐵))
8	7	eqeq1d 2738	. . . . . . . . . 10 ⊢ (𝐶 = ∅ → ((𝐶 ·o 𝐵) = ∅ ↔ (∅ ·o 𝐵) = ∅))
9	6, 8	syl5ibrcom 247	. . . . . . . . 9 ⊢ (𝐵 ∈ On → (𝐶 = ∅ → (𝐶 ·o 𝐵) = ∅))
10	9	necon3d 2953	. . . . . . . 8 ⊢ (𝐵 ∈ On → ((𝐶 ·o 𝐵) ≠ ∅ → 𝐶 ≠ ∅))
11	5, 10	syl5 34	. . . . . . 7 ⊢ (𝐵 ∈ On → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → 𝐶 ≠ ∅))
12	11	adantr 480	. . . . . 6 ⊢ ((𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → 𝐶 ≠ ∅))
13		on0eln0 6380	. . . . . . 7 ⊢ (𝐶 ∈ On → (∅ ∈ 𝐶 ↔ 𝐶 ≠ ∅))
14	13	adantl 481	. . . . . 6 ⊢ ((𝐵 ∈ On ∧ 𝐶 ∈ On) → (∅ ∈ 𝐶 ↔ 𝐶 ≠ ∅))
15	12, 14	sylibrd 259	. . . . 5 ⊢ ((𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → ∅ ∈ 𝐶))
16	15	3adant1 1131	. . . 4 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → ∅ ∈ 𝐶))
17	16	ancld 550	. . 3 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) ∧ ∅ ∈ 𝐶)))
18	4, 17	impbid2 226	. 2 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → (((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵) ∧ ∅ ∈ 𝐶) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))
19	3, 18	bitrd 279	1 ⊢ ((𝐴 ∈ On ∧ 𝐵 ∈ On ∧ 𝐶 ∈ On) → ((𝐴 ∈ 𝐵 ∧ ∅ ∈ 𝐶) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∧ w3a 1087   = wceq 1542   ∈ wcel 2114   ≠ wne 2932  ∅c0 4273  Oncon0 6323  (class class class)co 7367   ·_o comu 8403

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708  ax-rep 5212  ax-sep 5231  ax-nul 5241  ax-pr 5375  ax-un 7689

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-ral 3052  df-rex 3062  df-reu 3343  df-rab 3390  df-v 3431  df-sbc 3729  df-csb 3838  df-dif 3892  df-un 3894  df-in 3896  df-ss 3906  df-pss 3909  df-nul 4274  df-if 4467  df-pw 4543  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4851  df-iun 4935  df-br 5086  df-opab 5148  df-mpt 5167  df-tr 5193  df-id 5526  df-eprel 5531  df-po 5539  df-so 5540  df-fr 5584  df-we 5586  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-pred 6265  df-ord 6326  df-on 6327  df-lim 6328  df-suc 6329  df-iota 6454  df-fun 6500  df-fn 6501  df-f 6502  df-f1 6503  df-fo 6504  df-f1o 6505  df-fv 6506  df-ov 7370  df-oprab 7371  df-mpo 7372  df-om 7818  df-2nd 7943  df-frecs 8231  df-wrecs 8262  df-recs 8311  df-rdg 8349  df-oadd 8409  df-omul 8410

This theorem is referenced by:  omlimcl  8513  oneo  8516  omord2lim  43728  omord2com  43730