Closed Line Segment
# Definition
Let $V$ be a Vector Space over $\mathbb{R}$ and $x_{1}, x_{2} \in V$. The Closed Line Segment $L \subset V$ between $x_{1}$ and $x_{2}$ the Set $$L = {\lambda x_{1} + (1 - \lambda) x_{2} : \lambda \in [0,1]}$$
# Remarks
- $L$ can also be expressed as $L = {x_{2} + \lambda (x_{1} - x_{2}) : \lambda \in [0,1] }$. This follows from the observation that $$\lambda x_{1} + (1 - \lambda) x_{2} = x_{2} + \lambda x_{1} - \lambda x_{2} = x_{2} + \lambda (x_{1} - x_{2})$$