if-then-else is also a rule, like any other operation. The properties continous or differentiable come later.
You define when a function is continous or differentiable, you don't assume all functions continous and differentiable.
Am Samstag, 11. November 2017 14:31:11 UTC+1 schrieb John Gabriel: > Ever since I taught Jan Burse about Wolfram Computational Engine, he hasn't been able to get off it, reaching the wrong conclusions consistently! Chuckle. > > What a moron! I am beginning to think he is right down there with Dan Christensen.