I was good at secondary school maths, and got SOHCAHTOA and all that, but this visualisation would have help me understand it a lot better, and not be so scared

I was good at secondary school maths, and got SOHCAHTOA and all that, but this visualisation would have help me understand it a lot better, and not be so scared of the other things like COT. I didn't even learn COT at school, but knew of it's existence through BBC BASIC. Also I like this visualisation because it shows what we can easily do with SVG and JS (in this case Elm compiled to JS). It is a lot more powerful than Flash, but I don't see this kind of thing used much on the web, it would be good to see more of it, (for good uses of course)