Metamath Proof Explorer


Theorem rngosub

Description: Subtraction in a ring, in terms of addition and negation. (Contributed by Jeff Madsen, 19-Jun-2010)

Ref Expression
Hypotheses ringnegcl.1 G=1stR
ringnegcl.2 X=ranG
ringnegcl.3 N=invG
ringsub.4 D=/gG
Assertion rngosub RRingOpsAXBXADB=AGNB

Proof

Step Hyp Ref Expression
1 ringnegcl.1 G=1stR
2 ringnegcl.2 X=ranG
3 ringnegcl.3 N=invG
4 ringsub.4 D=/gG
5 1 rngogrpo RRingOpsGGrpOp
6 2 3 4 grpodivval GGrpOpAXBXADB=AGNB
7 5 6 syl3an1 RRingOpsAXBXADB=AGNB