Stages / 3
Stage 3 · about 12–15
Structure
Can we say it in general?
Negative numbers, algebra, equations, functions, geometric proof, probability.
All videos in this stage
- 15 Why Is a Negative Times a Negative Positive? Coming soon
- 16 Why Subtracting a Negative Means Adding Coming soon
- 17 (a+b)²: Where the Extra 2ab Comes From Planned
- 18 Difference of Squares: Cut and Paste Planned
- 19 Solving an Equation Is Balancing a Scale Planned
- 20 Why √2 Is Not a Fraction Planned
- 21 The Pythagorean Theorem: Rearrange and See Coming soon
- 22 Slope: How Steep Is a Line? Planned
- 23 Completing the Square, Literally Planned
- 24 Where Is the Vertex of a Parabola? Planned
- 25 Similar Triangles and Trigonometry Planned
- 36 Coin Flips: Why Frequencies Settle Down Planned