OK, boring. There is a cubic formula, too, that is a formula giving the solutions to a cubic equation. Almost no one is ever shown this cubic thing, let alone told why it works or who discovered it.

History is full of backstabbing rivalries: Edison and Tesla, Harding and Kerrigan, Tupac and Biggie. No less dramatic was a 16th-century conflict between Italian mathematicians Gerolamo Cardano, a ...