Shamelessly lifted from reddit:
Forty days pass, the flood recedes, and Noah and his family are settling in. Noah’s wife notices that all the animals are starting to reproduce, except for a pair of snakes. She asks Noah about it, and he says he’ll take care of it.
A week later, Noah brings his wife out to the workshop, and shows her the snakes in their basket on top of the picnic table he just built.
“How is this going to get them to reproduce?” she asks.
“Trust me,” he replies.
A few days after that, she notices there are eggs in the basket. She is delighted, and asks Noah how the picnic table could have possibly helped.
He says, “My dear, even adders can multiply on a log table.”
While on the topic of geeky math jokes:
There’s this calculus party, and all the functions are invited.
ln(x) is talking to some trig functions, when he sees his friend ex sulking in a corner.
ln(x): “What’s wrong ex?”
ex: “I’m so lonely!”
ln(x): “Well, you should go integrate yourself into the crowd!”
ex looks up and cries, “It won’t make a difference!”