Answer
a. $x = 0, 1, 4$
b. See graph
Work Step by Step
a. At the points $x=0$, $x=1$ and $x=4$, the function within the piecewise function changes, so the slope at that point is undefined. Since the point is at the intersection of the two functions, we cannot find the value of the derivative at this point.
b. Label the vertical axis as $y'$ then draw horizontal lines with $y$-values of the slope throughout the function. The $x$-values of the line drawn correlate to the $x$-values of the original graph.