Richland Community College
Richland Community College: Logarithmic Functions
This site from Richland Community College includes basic definition, properties, and graph of the logarithmic function.
CK-12 Foundation
Ck 12: Algebra Ii: 3.5 Using Logs to Solve Exponential Functions
This section explores logarithms as operations that are the inverse of exponents. It investigates the process for "undoing" or "eliminating" variable exponents when solving exponential equations.