What about sin(x) + 1?
I have a problem to figure out an example of primitive (antiderivative) function (as much simple as possible) which is NOT periodic function that is f(x+T)!=f(x) (where T is a period)
but it's derivative IS a periodic one.
I can proof the opposite case (use definition of derivative) if f(x) is periodic then it's derivative is also periodic, but according to a book which I'm studing now,
the opposite direction need not be true.
Thanks for help,