Description: Subtraction in a ring, in terms of addition and negation. (Contributed by Jeff Madsen, 19-Jun-2010)
Ref | Expression | ||
---|---|---|---|
Hypotheses | ringnegcl.1 | ||
ringnegcl.2 | |||
ringnegcl.3 | |||
ringsub.4 | |||
Assertion | rngosub |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ringnegcl.1 | ||
2 | ringnegcl.2 | ||
3 | ringnegcl.3 | ||
4 | ringsub.4 | ||
5 | 1 | rngogrpo | |
6 | 2 3 4 | grpodivval | |
7 | 5 6 | syl3an1 |