Real World Algebra: Exponential Functions


This unit is part of the special topic “Bringing the Real World into Algebra”. Students use dynamic geometry software to examine how exponential functions can model the features of real world contexts such as the curve of an ammonite fossil and data trends in world energy usage.


Lesson 1: Exponentials and Ammonites

Students use geometry and graphing technology to explore the relationships in the spacing of curves in the spiral of an ammonite fossil. They measure from an image, create tables of values, plot points, and fit functions, in the process exploring the roles of parameters in exponential functions.

Lesson 2: Modelling World Energy Production

This lesson uses technology to model the trend in world energy data (oil and wind). Students can explore the fit (by eye) of exponential functions to a large part of the data series then see that a trend may not continue for ever. In this task students consider what is and what is not exponential growth. Students link graphic and algebraic representations and interpret the functions rules developed in terms of their meaning as models of real world energy production.


Last updated December 11 2018.