2 out of 3
Can you make a square from these triangles?
2 out of 3
Which of these triangular jigsaws are impossible to finish?
2 out of 3
Starting with one of the mini-challenges, how many of the other mini-challenges will you invent for yourself?
2 out of 3
Can you work out the irrational numbers that belong in the circles to make the multiplication arithmagon correct?
3 out of 3
Given that a, b and c are natural numbers show that if sqrt a+sqrt b is rational then it is a natural number. Extend this to 3 variables.
3 out of 3
Show that there are infinitely many rational points on the unit circle and no rational points on the circle x^2+y^2=3.
3 out of 3
Can you work out where the blue-and-red brick roads end?
This article for pupils and teachers looks at a number that even the great mathematician, Pythagoras, found terrifying.
An introduction to proof by contradiction, a powerful method of mathematical proof.
