## Articles

**Jim Woodhouse**and

**Paul Galluzzo**explain why.

*Plus*, we heard how a simple mathematical equation became the subject of a debate in the UK parliament.

**Chris Budd**and

**Chris Sangwin**continue the story of the mighty quadratic equation.

**Lewis Dartnell**solves these, and other, puzzles of animal patterning.

**John Haigh**thinks that perhaps the publicity surrounding the lottery has enhanced the nation's numeracy.

**Chris Budd**and

**Chris Sangwin**tell us, in 2003 the good old quadratic equation, which we all learned about in school, reached these dizzy pinnacles of fame.

*Plus*, Marcus du Sautoy continues his exploration of the greatest unsolved problem of mathematics: The

**Riemann Hypothesis**.

**paper folding**.

**Calculus**is a collection of tools, such as differentiation and integration, for solving problems in mathematics which involve "rates of change" and "areas". In the first of two articles aimed specially at students meeting calculus for the first time, Chris Sangwin tells us about these tools - without doubt, the some of the most important in all of mathematics.