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 rewrites 100=10^2 as a logarithmic equation and log_5 (1/125)=-3 as an exponential equation. Created by Sal Khan.

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When you have an equation of the form a^x = b, taking the logarithm of both sides allows you to solve for x. This is particularly useful when dealing with exponential growth or decay problems.

So, log to the base 2 of 8 = x. 2*2*2 = 8, so x is 3. It's easy to find the answer with numbers that are small, such as 8, or with numbers you're comfortable with.

Learn how to solve any exponential equation of the form a⋅b^ (cx)=d. For example, solve 6⋅10^ (2x)=48.

Sal solves the equation log (x)+log (3)=2log (4)-log (2). Created by Sal Khan and Monterey Institute for Technology and Education.

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 …

Given a few points on the graph of an exponential function, Sal plots the corresponding points on the graph of the corresponding logarithmic function. Created by Sal Khan.