Description: Every additive subgroup of a non-unital ring is normal. (Contributed by AV, 25-Feb-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rngansg | |- ( R e. Rng -> ( NrmSGrp ` R ) = ( SubGrp ` R ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | rngabl | |- ( R e. Rng -> R e. Abel ) | |
| 2 | ablnsg | |- ( R e. Abel -> ( NrmSGrp ` R ) = ( SubGrp ` R ) ) | |
| 3 | 1 2 | syl | |- ( R e. Rng -> ( NrmSGrp ` R ) = ( SubGrp ` R ) ) |