Consider the cubic polynomial

MATHEMATICS · Multi-part · A Level · Mathematics · Differentiation · Differentiation

Problem

Consider the cubic polynomial g(x)=x3+ax2+bx+cg(x)=x^{3}+a x^{2}+b x+c, where aa, bb, and cc are real constants. Assume that gg has a relative maximum at x=−2x=-2 and a relative minimum at x=1x=1. (a) Derive the system of equations that aa and bb must satisfy based on the given information about the locations of the extrema. (b) Solve the system obtained in part (a) to determine the exact values of aa and bb. (c) Confirm that x=−2x=-2 is a relative maximum and x=1x=1 is a relative minimum by analyzing the sign of g′(x)g'(x) on the intervals determined by the critical points.

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