1. The problem statement, all variables and given/known data In my book it specifically asks to "find the points of inflection" of f (x) = 2x^3 + 9x^2 - 24x - 10. 2. Relevant equations f (x) = 2x^3 + 9x^2 - 24x - 10 f'(x) = 6x^2 + 18x - 24 f''(x) = 12x + 18. 3. The attempt at a solution What I don't get is why it asks for pointS. Isn't there just a single point here? Or can you get them not only by using the second derivative? I.e., set f"x = 0. Yet here only one point does that, not multiple ones? :S Could it be just a typo in the book?