Metamath Proof Explorer


Theorem opprneg

Description: The negative function in an opposite ring. (Contributed by Mario Carneiro, 5-Dec-2014) (Revised by Mario Carneiro, 2-Oct-2015)

Ref Expression
Hypotheses opprbas.1 O = opp r R
opprneg.2 N = inv g R
Assertion opprneg N = inv g O

Proof

Step Hyp Ref Expression
1 opprbas.1 O = opp r R
2 opprneg.2 N = inv g R
3 eqid Base R = Base R
4 eqid + R = + R
5 eqid 0 R = 0 R
6 3 4 5 2 grpinvfval N = x Base R ι y Base R | y + R x = 0 R
7 1 3 opprbas Base R = Base O
8 1 4 oppradd + R = + O
9 1 5 oppr0 0 R = 0 O
10 eqid inv g O = inv g O
11 7 8 9 10 grpinvfval inv g O = x Base R ι y Base R | y + R x = 0 R
12 6 11 eqtr4i N = inv g O