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Evaluating Logarithms

Evaluating Logarithms

Author: Zachary Olsen

F-LE 4.1: Prove simple laws of logarithms.

F-LE 4.3: Understand and use the properties of logarithms to simplify logarithmic numeric expressions and to identify their  approximate values.


This tutorial will target high school sophomores or advanced freshmen.  It is included in the Algebra II curriculum.

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The Basics

Study this basic introduction of what a logarithm is and how we write it mathematically.


The Basics

Source: Math Is Fun

Laws and Properties of Logarithms

Here is a quick reference/introduction to the laws and properties of logarithms.  They follow from exponential properties.

Laws and Properties

Source: uncw

Video Proof of Log addition

Source: Khan Academy

Video Proof of the Power Rule of Logs

Source: Khan Academy

Video Proof of Logarithmic Change of Base

Source: Khan Academy

Piecing It All Together

Apply what you have learned on the following practice problems.  This is all the preparation you will need for the tutorial's quiz.



"Big Picture" of tutorial

What is the relationship between logarithms and exponents?  How does this inform logarithmic properties and logarithmic evaluations?