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Lesson 11 of 16 · about 13 min

Counterexamples and disproof

Proving a "for all" claim takes a careful argument, but disproving one takes a single example. You'll learn what a counterexample is, why computers are brilliant at finding them, and hunt down the number that broke one of Goldbach's guesses.

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In this lesson you'll learn:

  • Counterexample
  • Disproving "there exists"

Free to try in F05 Logic & Proofs:

The first 3 lessons of every course are free, no account needed.