Cracking The Ap Calculus ab Exam 2018

SOLUTIONS TO PRACTICE PROBLEM SET 12

1. 2,000 ft^2 /s

We  are given   the rate    at  which   the circumference   is  increasing,     =   40  and are looking for

the rate    at  which   the area    is  increasing,  .  Thus,   we  need    to  find    a   way to  relate  the area    of  a

circle  to  its circumference.  Recall  that    the circumference   of  a   circle  is  C   =   2πr,    and the area    is