Metamath Proof Explorer


Theorem rngosub

Description: Obsolete theorem, use ringgrp and grpsubval instead. Subtraction in a ring, in terms of addition and negation. (Contributed by Jeff Madsen, 19-Jun-2010) (New usage is discouraged.) (Proof modification is discouraged.)

Ref Expression
Hypotheses ringnegcl.1 ⊢ G = 1 st ⁡ R
ringnegcl.2 ⊢ X = ran ⁡ G
ringnegcl.3 ⊢ N = inv ⁡ G
ringsub.4 ⊢ D = / g ⁡ G
Assertion rngosub ⊢ R ∈ RingOps ∧ A ∈ X ∧ B ∈ X → A D B = A G N ⁡ B

Proof

Step Hyp Ref Expression
1 ringnegcl.1 ⊢ G = 1 st ⁡ R
2 ringnegcl.2 ⊢ X = ran ⁡ G
3 ringnegcl.3 ⊢ N = inv ⁡ G
4 ringsub.4 ⊢ D = / g ⁡ G
5 1 rngogrpo ⊢ R ∈ RingOps → G ∈ GrpOp
6 2 3 4 grpodivval ⊢ G ∈ GrpOp ∧ A ∈ X ∧ B ∈ X → A D B = A G N ⁡ B
7 5 6 syl3an1 ⊢ R ∈ RingOps ∧ A ∈ X ∧ B ∈ X → A D B = A G N ⁡ B