Theorem mulpiord 10309

Description: Positive integer multiplication in terms of ordinal multiplication. (Contributed by NM, 27-Aug-1995.) (New usage is discouraged.)

Assertion

Ref	Expression
mulpiord	⊢ ((𝐴 ∈ N ∧ 𝐵 ∈ N) → (𝐴 ·N 𝐵) = (𝐴 ·o 𝐵))

Proof of Theorem mulpiord

Step	Hyp	Ref	Expression
1		opelxpi 5594	. 2 ⊢ ((𝐴 ∈ N ∧ 𝐵 ∈ N) → ⟨𝐴, 𝐵⟩ ∈ (N × N))
2		fvres 6691	. . 3 ⊢ (⟨𝐴, 𝐵⟩ ∈ (N × N) → (( ·o ↾ (N × N))‘⟨𝐴, 𝐵⟩) = ( ·o ‘⟨𝐴, 𝐵⟩))
3		df-ov 7161	. . . 4 ⊢ (𝐴 ·N 𝐵) = ( ·N ‘⟨𝐴, 𝐵⟩)
4		df-mi 10298	. . . . 5 ⊢ ·N = ( ·o ↾ (N × N))
5	4	fveq1i 6673	. . . 4 ⊢ ( ·N ‘⟨𝐴, 𝐵⟩) = (( ·o ↾ (N × N))‘⟨𝐴, 𝐵⟩)
6	3, 5	eqtri 2846	. . 3 ⊢ (𝐴 ·N 𝐵) = (( ·o ↾ (N × N))‘⟨𝐴, 𝐵⟩)
7		df-ov 7161	. . 3 ⊢ (𝐴 ·o 𝐵) = ( ·o ‘⟨𝐴, 𝐵⟩)
8	2, 6, 7	3eqtr4g 2883	. 2 ⊢ (⟨𝐴, 𝐵⟩ ∈ (N × N) → (𝐴 ·N 𝐵) = (𝐴 ·o 𝐵))
9	1, 8	syl 17	1 ⊢ ((𝐴 ∈ N ∧ 𝐵 ∈ N) → (𝐴 ·N 𝐵) = (𝐴 ·o 𝐵))

Syntax hints:   → wi 4   ∧ wa 398   = wceq 1537   ∈ wcel 2114  ⟨cop 4575   × cxp 5555   ↾ cres 5559  ‘cfv 6357  (class class class)co 7158   ·_o comu 8102  Ncnpi 10268   ·_N cmi 10270

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2795  ax-sep 5205  ax-nul 5212  ax-pr 5332

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1085  df-tru 1540  df-ex 1781  df-nf 1785  df-sb 2070  df-clab 2802  df-cleq 2816  df-clel 2895  df-nfc 2965  df-ral 3145  df-rex 3146  df-rab 3149  df-v 3498  df-dif 3941  df-un 3943  df-in 3945  df-ss 3954  df-nul 4294  df-if 4470  df-sn 4570  df-pr 4572  df-op 4576  df-uni 4841  df-br 5069  df-opab 5131  df-xp 5563  df-res 5569  df-iota 6316  df-fv 6365  df-ov 7161  df-mi 10298

This theorem is referenced by:  mulidpi  10310  mulclpi  10317  mulcompi  10320  mulasspi  10321  distrpi  10322  mulcanpi  10324  ltmpi  10328