Drexel dragonThe Math ForumDonate to the Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.

Math Forum » Discussions » Courses » ap-calculus

Topic: "Graphical" Period
Replies: 0  

Advanced Search

Back to Topic List Back to Topic List  
Al Coons

Posts: 898
Registered: 12/4/04
"Graphical" Period
Posted: Mar 6, 1998 7:02 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

The period of the sine function is 2Pi.

When plotting in the Cartesian plane we "see" this happening because f(x) =
sin(x+2Pi). Visually we look for the shortest "period" in which the values of
the function repeat itself. Of course, the period of the sine function is no
different when working with Polar Coordinates. r(theta) = sin(theta + 2Pi).
However, as you know, the polar plot of sin TRACES THE SAME POINTS with a
"graphical period" of Pi. This seems important to me. For example,
scientists might certainly want to know how often an particle passes a
detector as it follows a circular track. Questions:

1) Is there a formal name for what I have called "The Graphical Period of a

2) While we all note this when we teach polar plotting, is there a formal
study of this idea and even general formulae which apply across a large range
of functions?

3) Is this idea as important as it seems to me in applied mathematics,
science, traffic control,....?

Thanks in advance,

Albert Coons, Ph.D.
Buckingham Browne & Nichols School
Gerry's Landing Road
Cambridge, MA 02138
(617) 547-6100

Editor Technical Tips, "The Mathematics Teacher"
AP Statistics Web Site: www.bbns.org/us/math/ap_stats

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum 1994-2015. All Rights Reserved.