Composing music is a pretty mindful activity in its own right, but there’s certainly an argument to say that putting more focus on harmony, and thinking carefully about modulations between keys, can ...

In the diagram below, AB is the chord of a circle with centre O. OM is perpendicular to AB (meet at a right angle). Look at triangles OAM and OBM. The hypotenuses (OA and OB) are the same, as they are ...