Logarithms are the inverses of exponents. They allow us to solve challenging exponential equations, and they are a good excuse to dive deeper into the relationship between a function and its inverse.

Sal explains what logarithms are and gives a few examples of finding logarithms. Created by Sal Khan.

Algebra II on Khan Academy: Your studies in algebra 1 have built a solid foundation from which you can explore linear equations, inequalities, and functions.

Learn about the properties of logarithms that help us rewrite logarithmic expressions, and about the change of base rule that allows us to evaluate any logarithm we want using the calculator.

Sal explains what logarithms are and gives a few examples of finding logarithms.

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Test your knowledge of the skills in this course. You've seen inverse operations like multiplication and division. Because powers are not commutative, it takes two operations to undo them. Radicals let us …

Test your understanding of Exponential & logarithmic functions with these 38 questions.

Using logarithm tables, tedious multi-digit multiplication steps can be replaced by table look-ups and simpler addition. This is possible because the logarithm of a product is the sum of the logarithms of …

What you will learn in this lesson Logarithms, like exponents, have many helpful properties that can be used to simplify logarithmic expressions and solve logarithmic equations. This article explores three …