Polynomial discriminants. 2. Tensor diagrams

Recently I've been playing with diagrammatic ways of doing algebra and have come up with a lot of interesting results. This article presents the first of these - using tensor diagrams to compute discriminants of polynomials and to solve a related problem: line-curve tangency. I believe that the Einstein index notation can help us think about these and similar problems and allow us to come up with solutions that we wouldn't find any other way.