# Math Help - function is periodic

1. ## function is periodic

If a function is periodic with a period of K, then its derivative is periodic with the same period K.

A.
Mostly false, but is true once in awhile

B.
Mostly true, there are a few exceptions

C.
Always false, 100% of the time.

D.
Always True, 100% of the time

I selected B but was incorrect. I am leaning towards A on this one.

2. Let $x \in \mathbb{R}$.
What is $f'(x+K) =\lim_{h \to 0} \frac{f(x+K+h) - f(x+K)}{h}$?