\magnification=\magstep1
\nopagenumbers
\centerline{Mathematics 133 -- Intensive Calculus for Science, 1}
\centerline{Discussion 2 -- Periodicity}
\centerline{September 16, 2005}
\bigskip
\noindent
{\it Background}
\bigskip
The linear, exponential, and logarithm functions we have 
studied so far are  either always increasing or always
decreasing.  Not everything in the real world behaves this
way!  In particular, some processes or phenomena {\it repeat}
themselves.  For instance, some quantity
might increase for a while, decrease back to its starting 
point, then repeat the same pattern over and over again.
The length of time before 
the repetition starts is called the {\it period}.  Anything
that has this property is called {\it periodic}.
\bigskip
\noindent
{\it Discussion Questions}
\bigskip
\item{A)}  What are some examples of periodic things or processes in the real 
world. Try to think of at least three, and say what the period is in each 
case.
\bigskip

\item{B)}  We can also talk about {\it periodic functions} in mathematics.
 What would the {\it graph} of a periodic function of $x$
look like.  Try to draw one and indicate how the period 
is showing up in your graph.
\bye
