From 1973, an episode of Multiplication Rock (the first season of Schoolhouse Rock) complete with sponsorless opening and full Sunday credit roll. The song on the end credits is an instrumental version of "The Good Eleven".

A fun little song about how to find a derivative.
According to the Internet Archive, this video footage is from Irving "Kaps" Kaplansky's 80th Birthday Celebration on March 19, 1997 at the Mathematical Sciences Research Institute in Berkeley, CA.