Research-based guidance and classroom activities for teachers of mathematics


Proximity is a task on the NRICH website.

In what is sometimes called local deduction, pupils can utilise geometrical properties that they already know to deduce or explain other facts or results.

This task sets the challenge of proving a result in the context of a 3D shape. This requires visualisation, and the solution provides experience of proof by contradiction.

Go to Proximity on the NRICH website >>