spec / vectors.mdon commit start vector notes (cbe3d8d)
   1# Vectors
   2
   3- **vector:** a directed line segment  
   4- arrow indicates direction
   5- length indicates magnitude
   6- notated as $\vec{a}, \widetilde{A}, \overrightharp{a}$
   7
   8
   9![](graphics/vectors-intro.png)
  10
  11## Vector addition