Theorem rngmgp 20387

Description: A non-unital ring is a semigroup under multiplication. (Contributed by AV, 17-Feb-2020.)

Hypothesis

Ref	Expression
rngmgp.g	⊢ 𝐺 = (mulGrp‘𝑅)

Assertion

Ref	Expression
rngmgp	⊢ (𝑅 ∈ Rng → 𝐺 ∈ Smgrp)

Proof of Theorem rngmgp

Dummy variables 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		eqid 2760	. . 3 ⊢ (Base‘𝑅) = (Base‘𝑅)
2		rngmgp.g	. . 3 ⊢ 𝐺 = (mulGrp‘𝑅)
3		eqid 2760	. . 3 ⊢ (+g‘𝑅) = (+g‘𝑅)
4		eqid 2760	. . 3 ⊢ (.r‘𝑅) = (.r‘𝑅)
5	1, 2, 3, 4	isrng 20385	. 2 ⊢ (𝑅 ∈ Rng ↔ (𝑅 ∈ Abel ∧ 𝐺 ∈ Smgrp ∧ ∀𝑥 ∈ (Base‘𝑅)∀𝑦 ∈ (Base‘𝑅)∀𝑧 ∈ (Base‘𝑅)((𝑥(.r‘𝑅)(𝑦(+g‘𝑅)𝑧)) = ((𝑥(.r‘𝑅)𝑦)(+g‘𝑅)(𝑥(.r‘𝑅)𝑧)) ∧ ((𝑥(+g‘𝑅)𝑦)(.r‘𝑅)𝑧) = ((𝑥(.r‘𝑅)𝑧)(+g‘𝑅)(𝑦(.r‘𝑅)𝑧)))))
6	5	simp2bi 1164	1 ⊢ (𝑅 ∈ Rng → 𝐺 ∈ Smgrp)

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   = wceq 1569   ∈ wcel 2144  ∀wral 3076  ‘cfv 6543  (class class class)co 7424  Basecbs 17396  +_gcplusg 17437  ._rcmulr 17438  Smgrpcsgrp 18916  Abelcabl 20004  mulGrpcmgp 20369  Rngcrng 20383

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732  ax-nul 5259

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-sb 2099  df-clab 2739  df-cleq 2752  df-clel 2835  df-ne 2956  df-ral 3077  df-rab 3413  df-v 3452  df-sbc 3739  df-ss 3897  df-dif 4046  df-un 4150  df-nul 4278  df-if 4482  df-sn 4585  df-pr 4587  df-op 4835  df-uni 4867  df-br 5103  df-iota 6497  df-fv 6551  df-ov 7427  df-rng 20384

This theorem is used by:  rngmgpf  20388  rngass  20390  rngcl  20395  rng1zr  20413  isringrng  20525  isrnghmmul  20681  idrnghm  20697  c0rnghm  20796  cntzsubrng  20828  rnglidlmsgrp  21543