For the people who love Calculus
Here is a joke for the people who love Calculus.
Consider two functions f(x) = e^x, g(x) = c and the unknown differential operator D. Now, consider the following scenario:
g(x) is running down the street in a great panic when he runs into f(x).
f(x) : Hey constant function c. Whatís wrong?
g(x) : Oh, please help! Iím being chased by a differential operator!
f(x) : Donít worry constant function c, for I am e to the x. You can differentiate me, integrate me, because I don't care!
So then f(x) walks around the corner to face D.
f(x) : Hey you! Yes, you differential operator scum! Why are you bullying constant function c?
D____: What are you talking about?
f(x) : Who are you anyway?
D____: I'm called d/dy
Thus the story ends tragically due to the fact that
d/dy (e^x) = 0