Description: A two-sided ideal of a non-unital ring which is a subgroup of the ring is a normal subgroup of the ring. (Contributed by AV, 20-Feb-2025)
Ref | Expression | ||
---|---|---|---|
Hypotheses | rng2idlsubgsubrng.r | ||
rng2idlsubgsubrng.i | |||
rng2idlsubgsubrng.u | |||
Assertion | rng2idlsubgnsg |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rng2idlsubgsubrng.r | ||
2 | rng2idlsubgsubrng.i | ||
3 | rng2idlsubgsubrng.u | ||
4 | 1 2 3 | rng2idlsubgsubrng | |
5 | subrngringnsg | ||
6 | 4 5 | syl |