LessonPlans12

In this lesson I introduce the concept of exponential decay through the use of used car values. Similar problems are typically found in textbooks. I try to setup the problem in such a way that all of the information isn't given to the student right away. In the TI-Nspire file (and the accompanying spreadsheet) I've only given the students the first three years of values from the Kelly Blue Book website. The relationship looks linear at that point. When they find the linear relationship I then ask them to find the value of the car in 10 years (it's negative). We discuss why that is. Then, I give them the values for a few years after that to compare and now the relationship is clearly not linear. They know at this stage of the course that I can find exponential growth by comparing the growth in the y-column of an in-out table. Here, the differences are not arithmetic but geometric in nature. ||= [|TI-Nspire File]
 * =  ||< Description ||= File ||= Contributed by: ||= School SIte: ||
 * = 1 ||< __**Exponential Decay**__

[|Car Values] [|Spreadsheet] ||= Tony Alteparmakian ||= Foothill ||
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 * = 10 ||<  ||=   ||=   ||=   ||