# Ch 15: Understanding Exponential & Logarithmic Functions

### About This Chapter

## Understanding Exponential & Logarithmic Functions - Chapter Summary

This collection of calculus study resources covers essential concepts related to logarithmic and exponential functions. Inside the chapter, you'll find simple lessons that walk you through the steps needed to solve a variety of exponential and logarithmic function problems. You'll also examine concepts such as the change-of-base formula, the population dynamics problem, transformation and logarithmic properties. After completing the chapter, you should be able to:

- Define the terms exponential function, logarithm, natural log and natural base e
- Differentiate between exponential grown and decay
- Understand the transformation of exponential functions
- Write a logarithmic function's inverse
- Evaluate logarithms and recognize their properties
- Apply the change-of-base formula for logarithms
- Practice solving exponential and logarithmic equations
- Solve the population dynamics problem to calculate rate and exponential growth

To practice solving problems, take the self-assessment quizzes that follow each lesson. This way, you can be sure you fully understand these concepts and can solve these types of problems for a test. You'll be able to keep track of your progress throughout the chapter on your course Dashboard, which also allows you to jump to specific lesson topics. Feel free to submit questions to our instructors if you need extra help. Finally, the lesson material is available 24/7 and accessible on any device that has an Internet connection.

### 1. What Is an Exponential Function?

Brand new technologies don't always catch on right away because they can be expensive and don't always work as well as they should. But once the price comes down, and they start to work better, it doesn't take very long before it seems like everyone has one. Learn about the numbers behind this, exponential functions!

### 2. Exponential Growth vs. Decay

How is it that it only takes four years for our computer to go from top-of-the-line to almost worthless? Well, it has something to do with what's called exponential decay, which we'll learn about here!

### 3. Transformation of Exponential Functions: Examples & Summary

All exponential functions follow a basic graph. But when you make changes to the function, you will see the graph shift and make changes. Watch this video lesson to learn how to easily identify these changes or transformations.

### 4. Using the Natural Base e: Definition & Overview

In this video lesson, you will learn what kind of number 'e' is. Also learn the formal name for this unique number. See what kind of graph the natural base 'e' graphs into, as well as the uses of these types of functions.

### 5. What is a Logarithm?

Logarithms can help you solve exponential functions. In this lesson, you will learn about how to work with and recognize logarithms, and how to use logarithm notation with an example problem about earthquakes!

### 6. How to Evaluate Logarithms

Using this lesson, you can get practice evaluating logarithms, as well as learn some of the shortcuts behind writing and estimating them. You can also learn how to use your calculator to evaluate logarithms, and learn about a concept called the change of base theory.

### 7. Writing the Inverse of Logarithmic Functions

Watch this video lesson to learn how inverses are related to the original function. Also learn a method to find the inverse of logarithmic functions that you can easily use.

### 8. Exponentials, Logarithms & the Natural Log

Use the properties of exponentials and logarithms to learn how carbon dating works. This lesson covers properties of a natural log and rules of logarithms.

### 9. Basic Graphs & Shifted Graphs of Logarithmic Functions: Definition & Examples

Watch this video lesson and you will see what the basic graph of the logarithmic function looks like. You will also be able to identify the kind of shifts that will occur by just looking at a logarithmic function when you finish the video.

### 10. Logarithmic Properties

Along with the change of base property, there are three other logarithmic properties that allow you to manipulate expressions to your advantage. Learn about the product rule, quotient rule and power rule here.

### 11. Practice Problems for Logarithmic Properties

As you get further and further into mathematics, logarithms will appear more and more. It's the point of this lesson to get you used to dealing with them and able to know what to do when you see a whole line of paper full of them!

### 12. How to Solve Logarithmic Equations

If you're ever picking out a telescope to see your favorite planet, make sure you do the math first! Learn how to solve the logarithmic equation that will get you the size telescope you want.

### 13. Using the Change-of-Base Formula for Logarithms: Definition & Example

Logarithms have many uses in the real world. But what happens when the calculation uses a base other than the standard base 10? Watch this video to find out how to handle this situation and the formula to use.

### 14. How to Solve Exponential Equations

Read this lesson to learn the steps you need to take to solve exponential equations. You'll see that it's not too difficult; you just need to make use of one other mathematical operation in order to solve your problems.

### 15. Calculating Rate and Exponential Growth: The Population Dynamics Problem

You know how the world population keeps increasing? It's increasing faster now than it was 100 or 1,000 years ago. In this lesson, learn how differential equations predict this type of exponential growth.

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### Other Chapters

Other chapters within the Accuplacer Math: Advanced Algebra and Functions Placement Test Study Guide course

- Arithmetic with Rational Expressions
- Factoring in Algebra
- Expanding Polynomials
- Manipulating Roots
- Working with Exponents & Exponential Expressions
- Solving & Graphing Linear Equations
- Quadratic Equations
- Calculating & Graphing Inequalities
- Solving Systems of Linear Equations
- Geometric Angles & Shapes
- Line Theorems
- Similarity & Congruency in Geometry
- Pythagorean Theorem
- Graphs of Algebraic Functions
- Trigonometric Functions & Equations
- Accuplacer Math: Advanced Algebra and Functions Placement Test Flashcards