Determine Where the Graph of the Function $f(u)=\frac{3 u}{u^{2}-16}$ Is Concave Upward and Where It Is Concave Downward

Short Answer

Determine where the graph of the function $f(u)=\frac{3 u}{u^{2}-16}$ is concave upward and where it is concave downward. Also, find all inflection points of the function.