Important update, Jan. 17 at 18:00 UTC: There have been a lot of objections raised about the video mentioned below and the way I describe the math therein. It’s more than I can simply add or update ...

Yesterday, I posted an article about a math video that showed how you can sum up an infinite series of numbers to get a result of, weirdly enough, -1/12. A lot of stuff happened after I posted it.

I was having dinner with a visiting colleague this week when talk turned to what we were teaching this term. He mentioned the part of calculus dealing with infinite series (the bane of many students) ...

It's been a while since I wrote a post in this series, but since I've been teaching Calculus 2 this term the time is right. This all began when a former student wrote to ask how we know that those ...