| (1) | $X$ is a D11: Set |
| (2) | $d$ is a D58: Metric on $X$ |
| (3) | $\mathcal{T}_d$ is the D444: Metric topology on $X$ with respect to $d$ |
| (1) | $X$ is a D11: Set |
| (2) | $d$ is a D58: Metric on $X$ |
| (3) | $\mathcal{T}_d$ is the D444: Metric topology on $X$ with respect to $d$ |
| ▶ | D65: Cauchy sequence |
| ▶ | D4468: Empty metric space |
| ▶ | D47: Lipschitz map |
| ▶ | D1224: Set diameter |
| ▶ | D1400: Set distance |
| ▶ | D4475: Trivial metric space |
| ▶ | R708: Reverse triangle inequality for metric |