Lesson 4

1. Lesson 4

Mathematics 30-2 Module 7

Module 7: Exponents and Logarithms

Lesson 4: Characteristics of Logarithmic Functions

Focus

This is a photo of a monarch butterfly on a perennial aster flower.

Medioimages/Photodisc/Thinkstock

Researchers have discovered that the population of butterflies is dependent on the number of flower species that butterflies feed on. The relationship is a logarithmic function. As the number of flower species increase, so does the number of butterfly observations, but at a slower rate.

This is a graph of a curve increasing going from left to right. The horizontal axis is labelled “Number of Flower Species a Butterfly Feeds on” and the vertical axis is labelled “Number of Butterflies Observed.”

In this lesson you will learn the characteristics of logarithmic functions and their graphs, similar to the graph that shows the relationship between butterfly observations and number of flower species a butterfly feeds on.

Lesson Outcomes

At the end of this lesson, you will be able to

describe the characteristics of logarithmic functions by analyzing their graphs
describe the characteristics of logarithmic functions by analyzing their equations

Lesson Question

You will investigate the following question: How can the characteristics of logarithmic functions be described using graphs and equations?

Assessment

Your assessment may be based on a combination of the following tasks:

completion of the Lesson 4 Assignment (Download the Lesson 4 Assignment and save it in your course folder now.)
course folder submissions from Try This and Share activities
work under Project Connection