Needs splitting by mastery

Readers who come to Arbital pages with different levels of mathematical background require different pages to explain the same concept. Sometimes a page is written in a way that seems to cater for multiple audiences (e.g. having a careful wordy explanation designed for people with little background, then throwing out formulas and proofs that could only be followed by someone with much more background). In these cases, it’s often best to split the page into multiple lenses, designed for different math level audiences.