Metamath Proof Explorer


Theorem zringinvg

Description: The additive inverse of an element of the ring of integers. (Contributed by AV, 24-May-2019) (Revised by AV, 10-Jun-2019)

Ref Expression
Assertion zringinvg A A = inv g ring A

Proof

Step Hyp Ref Expression
1 zcn A A
2 1 negidd A A + A = 0
3 zringgrp ring Grp
4 id A A
5 znegcl A A
6 zringbas = Base ring
7 zringplusg + = + ring
8 zring0 0 = 0 ring
9 eqid inv g ring = inv g ring
10 6 7 8 9 grpinvid1 ring Grp A A inv g ring A = A A + A = 0
11 3 4 5 10 mp3an2i A inv g ring A = A A + A = 0
12 2 11 mpbird A inv g ring A = A
13 12 eqcomd A A = inv g ring A