∫ Утверждение Mathlib
mem_closedBall_iff_norm'''
Mathlib.Analysis.Normed.Group.Basic
URI: https://scilib.ai/kg/mathlib#mem_closedBall_iff_norm'''
∫ Утверждение Mathlib
Mathlib.Analysis.Normed.Group.Basic
URI: https://scilib.ai/kg/mathlib#mem_closedBall_iff_norm'''