Menu

Math Lesson 15.5.1 - What are Exponential Functions?

Please provide a rating, it takes seconds and helps us to keep this resource free for all to use

[ 1 Votes ]

Welcome to our Math lesson on What are Exponential Functions?, this is the first lesson of our suite of math lessons covering the topic of Exponential Graphs, you can find links to the other lessons within this tutorial and access additional Math learning resources below this lesson.

What are Exponential Functions?

In tutorial 7.1 and tutorial 13.2 we explained the meaning of the term 'exponent', which indicates the number of equal factors multiplied by each other in a recurring multiplication. For example, in the expression 24 = 16, the number 4 is the exponent, which shows how many equal factors (this common factor is called 'base' and in this specific case, the base is 2) multiply with each other to give the result, which we call 'power'.

The term 'exponential' derives from 'exponents', which we also call 'indices'. We have seen in tutorial 13.2 that exponential equations are those equations which have the variable in the exponent. Similarly, exponential functions are those functions that have the independent variable written as an index (exponent). The simplest form of exponential functions is

y(x) = ax

where a is a known number called the base. Recall the notation y(x), which is exclusively used in functions theory to indicate the dependent variable y in terms of the independent variable x but you can ignore it and write simply y instead of y(x).

However, the general form of an exponential function includes more terms than above. It contains a first-degree monomial in the exponent and a coefficient preceding the base a that multiplies the expression on the right side. Therefore, the general form of an exponential function is

y = k ∙ amx + t

It is clear that in the simplest form of exponential functions y = ax we have k = 1, m = 1 and t = 0.

Example 1

Find the values of a, k, m and t in the exponential function

y = 2 ∙ (34x - 2 + 1)

Solution 1

This function is not actually expressed in the standard form

y = k ∙ amx + t

so, the first thing to do is to transform it into the standard form. Thus, we write

y = 2 ∙ (34x - 2 + 1)
= 2 ∙ 34x - 2 + 2 ∙ 1
= 2 ∙ 34x ∙ 2-2 + 2 ∙ 1
= 2 ∙ 1/4 ∙ 34x + 2
= 1/2 ∙ 34x + 2

Comparing the last expression with the standard form of the exponential function we obtain the following values:

k = 1/2; a = 3; m = 4; and t = 2

You have reached the end of Math lesson 15.5.1 What are Exponential Functions?. There are 8 lessons in this physics tutorial covering Exponential Graphs, you can access all the lessons from this tutorial below.

More Exponential Graphs Lessons and Learning Resources

Types of Graphs Learning Material
Tutorial IDMath Tutorial TitleTutorialVideo
Tutorial
Revision
Notes
Revision
Questions
15.5Exponential Graphs
Lesson IDMath Lesson TitleLessonVideo
Lesson
15.5.1What are Exponential Functions?
15.5.2Exponential Function's Graph. Asymptotes of Exponential Graphs
15.5.3Plotting Exponential Graphs
15.5.4How the Value of the Base a Affects the Graph Shape?
15.5.5How do the Values of the Other Coefficients Affect the Graph?
15.5.6Finding the Formula of the Exponential Function from its Graph
15.5.7Exponential Graphs with Negative Base
15.5.8Exponential Graphs that Involve Euler's Number

Whats next?

Enjoy the "What are Exponential Functions?" math lesson? People who liked the "Exponential Graphs lesson found the following resources useful:

  1. Definition Feedback. Helps other - Leave a rating for this definition (see below)
  2. Types of Graphs Math tutorial: Exponential Graphs. Read the Exponential Graphs math tutorial and build your math knowledge of Types of Graphs
  3. Types of Graphs Revision Notes: Exponential Graphs. Print the notes so you can revise the key points covered in the math tutorial for Exponential Graphs
  4. Types of Graphs Practice Questions: Exponential Graphs. Test and improve your knowledge of Exponential Graphs with example questins and answers
  5. Check your calculations for Types of Graphs questions with our excellent Types of Graphs calculators which contain full equations and calculations clearly displayed line by line. See the Types of Graphs Calculators by iCalculator™ below.
  6. Continuing learning types of graphs - read our next math tutorial: Circle Graphs

Help others Learning Math just like you

Please provide a rating, it takes seconds and helps us to keep this resource free for all to use

[ 1 Votes ]

We hope you found this Math tutorial "Exponential Graphs" useful. If you did it would be great if you could spare the time to rate this math tutorial (simply click on the number of stars that match your assessment of this math learning aide) and/or share on social media, this helps us identify popular tutorials and calculators and expand our free learning resources to support our users around the world have free access to expand their knowledge of math and other disciplines.

Types of Graphs Calculators by iCalculator™