MATHEMATICS · Multi-part · AP · Calculus AB · Analytical Applications of Differentiation · Analytical Applications of Differentiation
Problem
Let f(x)=lnx for x>0 and consider the interval [1,e].
(i) Compute the average rate of change of f on [1,e].
(ii) Determine all real numbers c in (1,e) such that f′(c) equals the average rate obtained in part (i).
(iii) Prove that exactly one such number c exists in (1,e).