MATHEMATICS · Multi-part · AP · Calculus AB · Differentiation: Composite, Implicit, and Inverse Functions · Differentiation: Composite, Implicit, and Inverse Functions
Problem
For k∈R, consider the function y=(x2+kx+1)3.
(i) Find dx2d2y in terms of x and k.
(ii) Determine the value of k for which dx2d2y equals zero at x=1.
(iii) For the value of k obtained in part (ii), decide whether the curve has an inflection point at x=1, giving reasons for your answer.