An interesting area of mathematics is graph theory, and it deals with a simple question: how do things connect together? In graph theory, we’re interested in vertices (also called nodes) that have relationships with other nodes. These relationships are called edges (or branches), and with these two ideas, we can explore many different and interesting problems. However, the reason I’m bringing this up now is that I’ve been watching a superb series of videos that explain the workings of graph theory, and I wanted to both share the series and comment on some of the problems. To do this, we’ll have to go through a bit of the theory to ground ourselves comfortably, though we won’t go into enormous depth.

When I was younger and first going through the “jump” between secondary mathematics and physics to that of CÉGEP and university, I always got frustrated when teachers would just shrug their shoulders when we grumbled about having too many things to remember for the test. Their advice was to simply remember the fundamentals, and rederive any result that was needed afterward.

If you’ve ever learned logic, you know that jumping from one piece of information to another (through implication) isn’t always clear. You might remember something about if A implies B, then not B implies not A, and the like. What I want to do today is try and explore these concepts in a more visual way, which hopefully will let you remember these concepts with greater ease.

When students first start working in mathematics, units aren’t really something to worry about. Indeed, students begin with doing arithmetic, where there’s little need for extra fuss about units. Students get used to writing equations without ever thinking about units.