The topic: power series. I was showing how to manipulate the relation to get power series of various kinds, including series centered at values other than zero. For example, if one wanted the series centered at, say, we could write .
And so I said: Let’s try to find the series for centered at . And. I. Was. Not. Able. To. Do. It.
So I went on to another problem…and it hit me.
O. M. G. (slamming my head on the desk here…dying of embarrassment).
Moral: never get overconfident. 🙂
Yes, I told the class of my blunder as soon as it hit me; they laughed…with me, I think. 😉