3B1B - Chapter 1
Chapter 1 discussed the Vector; a list of numbers that is used to represent an arrow in a coordinate system.
It is written vertically with the x-coordinate on top of the y-coordinate. Both numbers represent the distance from the center of the coordinate system.
Chapter 1 also introduced the notion of the Scalar which comes in play when we scale a vector. A negative scalar will mirror the vector onto the negative axis. A number lower than 1 will scale a vector down, vice versa a number bigger than 1 will scale a vector up.