Khan Academy: Logarithm Properties: Proof: Log a + Log B = Log Ab

Sal gets to the heart of this video, clarifying that it's important to understand math "so you can apply it later on and not have to relearn everything every time." True to his word, Sal demonstrates ways to solve logs and exponents more...

This video proves the helpful change of base formula for logarithms. The proof steps may need to be more intuitive to most logarithm learners, but the algebraic manipulation shown using logs is interesting.

Proofs of the logarithm properties: A(log B) = log (B^A) and log A - log B = log (A/B)

Explore logarithm properties through change of base formula proofs.

Introduction to the first two logarithm properties.

Explore logarithm properties through change of base formula.

Logarithm of a Power

Using Multiple Logarithm Properties to Simplify

Sum of Logarithms with Same Base

The basics of the logarithmic Richter and Moment Magnitude Scales to measure earthquakes