MATHEMATICS · Multi-part · AP · Calculus AB · Limits and Continuity · Limits and Continuity
Problem
Let
h(x)=x−4∣x−4∣(x2−16)(x=4),
and define h(4)=k, where k is a constant. Use a combination of algebraic techniques and limit properties to answer the following.
(1) Compute x→4−limh(x) and x→4+limh(x) separately, showing each algebraic step.
(2) Determine whether the one-sided limits you found in part (a) are equal. If they are equal, state their common value; if not, explain why they differ.
(3) Find the value of k that makes h continuous at x=4. Justify your answer using your results from parts (a) and (b).
(4) Provide a brief written justification that each algebraic step you used in parts (a) and (b) is valid for evaluating a limit, citing appropriate limit properties.