Inflection Point

For the curve represented by the equation below, what value of x does the only point of inflection occurs at?

First, find the second derivative of $$f(x)$$ .
Hint 2
Set $$f''(x)=0$$ to solve for the inflection point.
An inflection point is a point on the curve/graph at which concavity changes, and occurs when $$f''(x)=0$$ .
Using the power rule for the first derivative and applying it twice, we’ll get the second derivative power rule:
Thus, the second derivative is:
Solving for $$x$$ when $$f''(x)=0$$ to get the x-component inflection point:
Since $$f''(x)=0$$ and $$f''(x)$$ changes signs at $$x=-1/3$$ , the inflection point is at $$x=-1/3$$ .