Index Of X Jpg How To Find Deriative Y = F'(x) Of A Function Y=f(x) With A Given Graph?

How to find deriative y = f'(x) of a function y=f(x) with a given graph? - index of x jpg

as a table like this (pretend that is f (x)
http://demonstrations.wolfram.com/PolynomialGraphGenerator/HTMLImages/index.en/popup_4.jpg
How can we f '(x)-see curve Notes ....