ap-calculus-ab None Q2 (Free-Response)
Analyze function behavior from graph or table of derivative
The figure above shows the graph of $f ^ { \prime }$, the derivative of a twice-differentiable function $f$, on the closed interval $[ 0,4 ]$. The areas of the regions bounded by the graph of $f ^ { \prime }$ and the $x$-axis on the intervals $[ 0,1 ] , [ 1,2 ] , [ 2,3 ]$, and $[ 3,4 ]$ are $2, 6, 10$, and $14$, respectively. The graph of $f ^ { \prime }$ has horizontal tangents at $x = 0.6 , x = 1.6$, $x = 2.5$, and $x = 3.5$. It is known that $f ( 2 ) = 5$.
(a) On what open intervals contained in $( 0,4 )$ is the graph of $f$ both decreasing and concave down? Give a reason for your answer.
(b) Find the absolute minimum value of $f$ on the interval $[ 0,4 ]$. Justify your answer.
(c) Evaluate $\int _ { 0 } ^ { 4 } f ( x ) f ^ { \prime } ( x ) \, d x$.
(d) The function $g$ is defined by $g ( x ) = x ^ { 3 } f ( x )$. Find $g ^ { \prime } ( 2 )$. Show the work that leads to your answer.