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Mathematics

Constructing a Proof by Induction Step by Step

Quick fact

Induction works like toppling dominoes: if you push the first one, and each domino knocks over the next, then all of them fall. It was first explicitly used by Francesco Maurolico in 1575 to prove that the sum of the first n odd numbers is n².

Why this is interesting

You might think proving something is true for an infinite number of cases is impossible. But with induction, you can do it in just two steps—what's the trick?