Maths is full of cool theorems. The Pigeonhole Principle is one of my favourites because of the fact that it is so powerful and quite tricky to prove, yet so intuitive and easy to understand. Before I can talk about it though, I need to introduce you to the world of mathematical functions. Functions In maths, a function is a ‘mapping’ from one ‘space’ to another. The ones that people are used to seeing are things like f(x) = x2 […]