A4 Show that ! f(x) is odd. Show Instructions In general, you can skip the multiplication sign, so `5x` is equivalent to `5*x`. Section 4-4 : Finding Absolute Extrema. MasterMathMentor. Inflection point: " The x -value where the curve switches concavity. " So you also need to look at $(x,27)$ for $-3\sqrt{3}