yep, that's what I pointed out in my last post, only less elaborate. It's quite difficult to explain mathematics in a foreign language. There are so many special terms you never learned at school.
Totally off-topic, but I just have to ask: what kind of spider is the one in your avatar, Asbo Zaprudder? It's pretty!
A jumping spider - family Salticidae - although I'm not sure which one of the approx 5000 species.