:PROPERTIES: :ID: ab024db7-6903-48ee-98fc-b2a228709c04 :ROAM_ALIASES: vector linear "linear space" :END: #+title: vector space #+author: Preston Pan #+html_head: #+html_head: #+html_head: #+options: broken-links:t * Introduction A vector space $V$ is a set with addition and scalar multiplication defined. It obeys the following axioms: \begin{align} \label{} \vec{a} + (\vec{b} + \vec{c}) = (\vec{a} + \vec{b}) + \vec{c} \\ \vec{a} + \vec{b} = \vec{b} + \vec{a} \\ \exists \vec{0},\forall \vec{a}, \vec{a} + \vec{0} = \vec{a} \\ \forall \vec{a},\exists\vec{-a}, \vec{a} + \vec{-a} = \vec{0} \\ (cd)\vec{a} = c(d\vec{a}) \\ 1\vec{a} = \vec{a} \\ c(\vec{a} + \vec{b}) = c\vec{a} + c\vec{b} \\ (c + d)\vec{a} = c\vec{a} + d\vec{a} \end{align} vector spaces are an Abelian [[id:ba7b95b0-0ce6-4b33-9a79-5e5fddaea710][group]] under addition. $\vec{a}$, $\vec{b}$, and $\vec{c}$ are considered vectors so long as they fulfill these properties.