Lesson 3.1 · 13 of 25 lessons

Dot products & orthogonality

Carry the right angle created by a dot product into projection and least-squares error.

Open the interactive animation

01 · Story

What to verify in this scene

Follow the explanations and operations, then identify the mathematical evidence that remains in the final scene.

  1. 01

    The dot product measures how much two vectors face the same direction

  2. 02

    dot(u, v) = 0
    The two vectors are orthogonal

02 · Notebook

The runnable notebook

This source creates the mathematical objects and controls the order of operations and animation. Read it here, then play the same scene yourself.

2d
zoom 1
coordinates on

2, 1  #u@
-1, 2  #v@
// The **dot product** measures how much two vectors face the same direction
focus u v
checkpoint Dot products & orthogonality

focus -
dot(u, v)  #d@
// `dot({{u}}, {{v}}) = 0`\nThe two vectors are **orthogonal**
focus u v
Open the interactive animation

03 · Unit 3

Lessons in this unit

Orthogonality, projection & least squares — Carry the right angle created by a dot product into projection and least-squares error.

  1. 3.1Dot products & orthogonality
  2. 3.2Projection
  3. 3.3Least squares