Pierre Wantzel

Pierre Laurent Wantzel (5 June 1814 – 21 May 1848) was a French mathematician. He discovered important things about what we can and cannot do with just a compass and straightedge.

In 1837, Wantzel proved that two famous old puzzles—doubling the cube and trisecting the angle—cannot be solved with those simple tools. He also showed which regular polygons are constructible. This depends on the number of sides being a power of two times special primes called Fermat primes.

These puzzles had puzzled people for thousands of years, especially the ancient Greeks. Wantzel’s work was not appreciated at first. It was almost forgotten until later when other mathematicians saw its importance. In 1843, Wantzel also discovered something about equations. He showed that some solutions need complex numbers, even when the answers look simple.

Wantzel’s life was sadly short. He died at the age of 33. Even though his work was not always recognized when he lived, today he is remembered for solving problems that had puzzled mathematicians for centuries.