Jump to page content Jump to navigation

College Board

AP Central

AP Online Score Reporting
Be an AP Exam Reader
Siemens Awards for Advanced Placement
Click here to visit the SpringBoard Microsite
Print Page
Home > AP Courses and Exams > Course Home Pages > AP Calculus Question of the Month: August

AP Calculus Question of the Month: August

by Lin McMullin
Educational Consultant and Writer
Niantic, Connecticut

My favorite function is  . Get out your graphing calculator and see if you can answer my favorite question about my favorite function: How many roots does  have in the half-open interval  ?

Try it now.

Okay, I misled you about the calculator. That was on purpose. There are an infinite number of roots in the interval. Your calculator can show you one, occasionally two, but never more than two at a time on a single screen. Don't throw out your calculator; even powerful, computer-based graphing programs cannot do much better.

So here's this month's real question:

Find all the roots of  in the interval  . Explain why any graphing calculator or computer program cannot produce a graph that shows more than two of these roots in any graphing window or computer screen.

I like to use this problem at the beginning of the year or when discussing graphing calculator use with teachers. A full explanation will lead you to review several different mathematical concepts. You can use this question at the beginning of the year to review some major topics from precalculus mathematics. This question is also useful to lead a discussion of how calculators and computers draw graphs and of the limitations of such graphs.

Complete the question before viewing the the answers and commentary!








  ABOUT MY AP CENTRAL
    Course and Email Newsletter Preferences
  AP COURSES AND EXAMS
    Course Home Pages
    Course Descriptions
    The Course Audit
    Teachers' Resources
    Exam Calendar and Fees
    Exam Information
    FAQs
  PRE-AP
    SpringBoard® Pre-AP Program
    Workshops
    Teachers' Corner
  AP COMMUNITY
    About Electronic Discussion Groups
    Become an AP Exam Reader

Back to top