Why is the integral of 1/cabin a nice place to be?
Because it's a natural log cabin, beside the 'c'....
Also not really a 'joke' but maths chatup lines:
"hey baby, I wish you were my derivative so I could lay tangent to your curves"
"...why don't you be Sin^2 x, and I'll be Cos^2 x, and together we can be 1..."
Who says maths can't be fun?!!