Description: A Banach space is a normed group. (Contributed by Mario Carneiro, 15-Oct-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | bnngp | |- ( W e. Ban -> W e. NrmGrp ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | bnnlm | |- ( W e. Ban -> W e. NrmMod ) |
|
| 2 | nlmngp | |- ( W e. NrmMod -> W e. NrmGrp ) |
|
| 3 | 1 2 | syl | |- ( W e. Ban -> W e. NrmGrp ) |