math nerds unite

smudgeofashenfluff  asked:

(RE requests to your blog.) A while ago after I'd taken a few years of Calculus (nothing too advanced), I was frustrated at the vague and ambiguous definitions of "differentials" (dx, dy). I learned from the literature that it IS somewhat of an illusive concept. Another mystery that I was on a quest to understand was the "physical manifestation" of composite functions and the Chain Rule. HOW they work on a deep level. I halted my research in the middle but may return some day. Do these appeal?

I hope I’ve answered your question here: http://tomsmathclass.blogspot.com/2011/10/differentialsthe-elusive-concept.html

Or, at least, the “differential” part of it.  I hope you’ll forgive me for editing your question: Composite functions is a subject I have to research a little more, and I need to refresh myself on the chain rule (don’t even get me started on L'Hôpital’s Rule <shudder>).