A physicist and a mathematician sitting in a faculty lounge. Suddenly, the coffee machine catches on fire. The physicist grabs a bucket and leaps towards the sink, fills the bucket with water and puts out the fire. The second day, the same two sit in the same lounge. Again, the coffee machine catches on fire. This time, the mathematician stands up, gets a bucket, hands the bucket to the physicist, thus reducing the problem to a previously solved one.
Two mathematicians were having dinner in a restaurant, arguing about the average mathematical knowledge of the American public. One mathematician claimed that this average was woefully inadequate, the other maintained that it was surprisingly high. "I'll tell you what," said the cynic, "ask that waitress a simple math question. If she gets it right, I'll pick up dinner. If not, you do". He then excused himself to visit the men's room, and the other called the waitress over. "When my friend comes back," he told her, "I'm going to ask you a question, and I want you to respond `one third x cubed.' There's twenty bucks in it for you." She agreed. The cynic returned from the bathroom and called the waitress over. "The food was wonderful, thank you," the mathematician started. "Incidentally, do you know what the integral of x squared is?" The waitress looked pensive; almost pained. She looked around the room, at her feet, made gurgling noises, and finally said, "Um, one third x cubed?" So the cynic paid the check. The waitress wheeled around, walked a few paces away, looked back at the two men, and muttered under her breath, "...plus a constant."
What's purple and commutes? An abelian grape.
The internet is full of this stuff:
https://www.juliantrubin.com/mathjokes.html
Also, here's one of my favorite pages on the whole web. It was last updated in 2002:
http://www.mit.edu/~jcb/other-instrument-jokes.html
What do you say to a banjo player in a three-piece suit?
"Will the defendant please rise?"
(I know this is off topic, but that's the forum, eh?)