How to solve this equation?

[Jehanne]

mathematical spy that was caught because he was told the sine and didn't know the cosine.

I don't understand that joke either.

Then there are the snakes on Noah's arc that didn't go forth to multiply be cause they were adders. But later, they had kids beside a fallen tree: adders can multiply by logs.

I think I understand it, but I don't find it funny.

Then there is the proof that all horses are the same color (by induction). And the proof (like that above for dogs) that horses have at least 12 legs, which gives a horse of a different color, a contradiction.

Sorry, I do not understand what you are saying. If that was supposed to be funny, it is not.

Short of risque, it's the best that mathematicians (or anyone else), given the subject matter, can do.