Metamath Proof Explorer


Theorem ringnegl

Description: Negation in a ring is the same as left multiplication by -1. ( rngonegmn1l analog.) (Contributed by Jeff Madsen, 19-Jun-2010) (Revised by Mario Carneiro, 2-Jul-2014)

Ref Expression
Hypotheses ringnegl.b B=BaseR
ringnegl.t ·˙=R
ringnegl.u 1˙=1R
ringnegl.n N=invgR
ringnegl.r φRRing
ringnegl.x φXB
Assertion ringnegl φN1˙·˙X=NX

Proof

Step Hyp Ref Expression
1 ringnegl.b B=BaseR
2 ringnegl.t ·˙=R
3 ringnegl.u 1˙=1R
4 ringnegl.n N=invgR
5 ringnegl.r φRRing
6 ringnegl.x φXB
7 1 3 ringidcl RRing1˙B
8 5 7 syl φ1˙B
9 ringgrp RRingRGrp
10 5 9 syl φRGrp
11 1 4 grpinvcl RGrp1˙BN1˙B
12 10 8 11 syl2anc φN1˙B
13 eqid +R=+R
14 1 13 2 ringdir RRing1˙BN1˙BXB1˙+RN1˙·˙X=1˙·˙X+RN1˙·˙X
15 5 8 12 6 14 syl13anc φ1˙+RN1˙·˙X=1˙·˙X+RN1˙·˙X
16 eqid 0R=0R
17 1 13 16 4 grprinv RGrp1˙B1˙+RN1˙=0R
18 10 8 17 syl2anc φ1˙+RN1˙=0R
19 18 oveq1d φ1˙+RN1˙·˙X=0R·˙X
20 1 2 16 ringlz RRingXB0R·˙X=0R
21 5 6 20 syl2anc φ0R·˙X=0R
22 19 21 eqtrd φ1˙+RN1˙·˙X=0R
23 1 2 3 ringlidm RRingXB1˙·˙X=X
24 5 6 23 syl2anc φ1˙·˙X=X
25 24 oveq1d φ1˙·˙X+RN1˙·˙X=X+RN1˙·˙X
26 15 22 25 3eqtr3rd φX+RN1˙·˙X=0R
27 1 2 ringcl RRingN1˙BXBN1˙·˙XB
28 5 12 6 27 syl3anc φN1˙·˙XB
29 1 13 16 4 grpinvid1 RGrpXBN1˙·˙XBNX=N1˙·˙XX+RN1˙·˙X=0R
30 10 6 28 29 syl3anc φNX=N1˙·˙XX+RN1˙·˙X=0R
31 26 30 mpbird φNX=N1˙·˙X
32 31 eqcomd φN1˙·˙X=NX