Definitions:

1. log_a x = y means that a^y = x
2. log x means log₁₀ x
3. ln x means log_e x, where e is about 2.718

A general example to help you recognize patterns and spot the information you're looking for

log₂16 = log₂8 + log₂2

log_b(5/2) = log_b5 - log_b2

log₂(6⁵) = 5 log₂6

log₂5 = log₃5 / log₃2

log₅1 = 0

log₃3 = 1

log_bb² = 2

8^log8² = 2

Introduction to Logarithms

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Length: 9:49

Introduction to Logarithm Properties

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Length: 9:16

Introduction to Logarithm Properties (part 2)

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Length: 10:05

Solving Logarithmic Equations

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Length: 4:13

Simplifying Logarithms »

Operations with Logarithms »