Khan Academy on a Stick
Logarithms
Logawhat? No, this tutorial is about neither chopped wood nor music (actually logarithms do have applications in music), but it is fascinating nonetheless. You know how to take an exponent. Now you can think about what exponent you have to raise a number to to get another number. Yes, I agreeunstoppable fun for the whole family. No, seriously, logarithms are used everywhere (including to measure earthquakes and sound).

Logarithms
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Intro to logarithms. Learning that logarithms are just a way of expressing "the exponent that you have to raise a base to to get another number"

Ex: Converting an exponential to logarithmic statement
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Logarithmic Equations 2

Fancier logarithm expressions
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Examples of logarithms that evaluate to fractional and negative values.

Graphing Logarithmic Functions
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Graphing Logarithmic Functions

Introduction to Logarithms
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An introduction to logarithms
Logarithm basics
If you understand how to take an exponent and you're looking to take your mathematical game to a new level, then you've found the right tutorial. Put simply and confusingly, logarithms are inverse operators to exponents (just as subtraction to addition or division to multiplication). As you'll see, taking a logarithm of something tells you what exponent you need to raise a base to to get that number.

Introduction to logarithm properties
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Introduction to the first two logarithm properties.

Introduction to logarithm properties (part 2)
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Second part of the introduction to logarithm properties.

Logarithm of a Power
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Logarithm of a Power

Sum of Logarithms with Same Base
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Sum of Logarithms with Same Base

Using Multiple Logarithm Properties to Simplify
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Using Multiple Logarithm Properties to Simplify

Change of Base Formula
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Change of Base Formula

Proof: log a + log b = log ab
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Proof of the logarithm property: log a + log b = log ab

Proof: A(log B) = log (B^A), log A  log B = log (A/B)
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Proofs of the logarithm properties: A(log B) = log (B^A) and log A  log B = log (A/B)
 Change of base formula proof

Logarithmic Equations
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Logarithmic Equations

Solving Logarithmic Equations
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Solving Logarithmic Equations

Solving Logarithmic Equations
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Solving Logarithmic Equations

Logarithmic Scale
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Understanding how logarithmic scale is different from linear scale and why it could be useful

Richter Scale
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The basics of the logarithmic Richter and Moment Magnitude Scales to measure earthquakes
Logarithm properties
You want to go deeper in your understanding of logarithms. This tutorial does just that by exploring properties of logarithms that will help you manipulate them in entirely new ways (mostly falling out of exponent properties).

Natural Logarithm with a Calculator
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Natural Logarithm with a Calculator

Calculator for Natural Logarithms
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Calculator for Natural Logarithms

Graphing Natural Logarithm Function
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Graphing Natural Logarithm Function
Natural logarithms
e is a special number that shows up throughout nature (you will appreciate this more and more as you develop your mathematical understanding). Given this, logarithms with base e have a special namenatural logarithms. In this tutorial, we will learn to evaluate and graph this special function.