This article for pupils and teachers looks at a number that even the great mathematician, Pythagoras, found terrifying.
Using the interactivity, can you make a regular hexagon from yellow triangles the same size as a regular hexagon made from green triangles ?
Read all about Pythagoras' mathematical discoveries in this article written for students.
If the yellow equilateral triangle is taken as the unit for area, what size is the hole ?
An introduction to proof by contradiction, a powerful method of mathematical proof.
What fractions can you find between the square roots of 65 and 67?
Ranging from kindergarten mathematics to the fringe of research this informal article paints the big picture of number in a non technical way suitable for primary teachers and older students.
Tim Rowland introduces irrational numbers
How many differently shaped rectangles can you build using these equilateral and isosceles triangles? Can you make a square?
Can you express every recurring decimal as a fraction?