Answer
The function is increasing on the inerval $[-\infty;b]$ and decreasing on the interval of $[b;\infty]$.
The function is concave up on the interval of $[-\infty;0]$
The function is concave down on the interval of $[0;a]$
The function is concave up on the interval of $[a;\infty]$
Work Step by Step
The function is increasing on the inerval $[-\infty;b]$ and decreasing on the interval of $[b;\infty]$.
The function is concave up on the interval of $[-\infty;0]$, as the graph forms an upside-down letter 'U', which is exactly the form of a concave up function.
The function is concave down on the interval of $[0;a]$, as the graph forms a letter 'U', which is exactly the form of a concave down function.
The function is concave up on the interval of $[a;\infty]$, as the graph forms an upside-down letter 'U', which is exactly the form of a concave up function.
