Math · Beginner · 4 steps

The Proof Einstein Found at Twelve

Taught by Einstein · Playful thought experiments

The Pythagorean theorem seen three ways: count the tiles on the squares of a right triangle, slide four triangles to see a² + b² = c² without an equation, and follow the similar-triangles proof Einstein found for himself at twelve.

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Free, no account needed. Opens right here; the same lesson runs in the app with narration in Einstein's voice.

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What you will learn

  • Counting tiles on the squares of a right triangle
  • Seeing a² + b² = c² by rearranging four triangles
  • The similar-triangles proof Einstein found at twelve
  • Testing yourself with three questions

Lesson outline

  1. Count the Tiles
  2. Slide the Triangles
  3. Einstein's Proof at Twelve
  4. A Small Thought Experiment

Each step has a short narration, something to drag or toggle, and the lesson ends with a quiz. You can go back to any step.

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