Answer
The graph is either concave down or concave up everywhere.
There are no inflections, cusps, or corners.
Work Step by Step
If $ f''(x) \gt 0 $ on the whole domain, then $f$ is concave up, and never changes concavity.
This means: no inflections, no cusps, no corners.
The same goes if $ f''(x) \lt 0 $ on the whole domain, except that it is concave down everywhere.
