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Evaluating logarithms using change-of-base formula
- Lesson: 13:21
- Lesson: 2a1:04
- Lesson: 2b1:09
- Lesson: 2c1:21
- Lesson: 2d1:41
- Lesson: 3a3:11
- Lesson: 3b6:47
Evaluating logarithms using change-of-base formula
Basic Concepts: Converting from logarithmic form to exponential form, Evaluating logarithms without a calculator, Common logarithms
Related Concepts: Logarithmic scale: Richter scale (earthquake), Logarithmic scale: pH scale, Logarithmic scale: dB scale
Lessons
• change-of-base rule:logba=logxblogxa=logbloga
• common logarithms:log with base ‘‘10"example: log3=log103
example: logx=log10x
• common logarithms:log with base ‘‘10"example: log3=log103
example: logx=log10x
- 1.How to apply ‘‘change-of-base rule"
Express log53 in three different ways. - 2.Using a calculator, evaluate the following logarithms
by applying ‘‘ change-of-base rule":a)log53b)log7416c)log2257d)6log4999 - 3.Using a calculator, solve for x to the nearest hundredth.a)log6x=log78b)log235=logx0.104
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19.
Logarithms
19.1
What is a logarithm?
19.2
Converting from logarithmic form to exponential form
19.3
Evaluating logarithms without a calculator
19.4
Common logarithms
19.5
Natural log: ln
19.6
Evaluating logarithms using change-of-base formula
19.7
Converting from exponential form to logarithmic form
19.8
Solving exponential equations with logarithms
19.9
Product rule of logarithms
19.10
Quotient rule of logarithms
19.11
Combining product rule and quotient rule in logarithms
19.12
Evaluating logarithms using logarithm rules
19.13
Solving logarithmic equations
19.14
Graphing logarithmic functions
19.15
Finding a logarithmic function given its graph
Don't just watch, practice makes perfect
Practice topics for Logarithms
19.1
What is a logarithm?
19.2
Converting from logarithmic form to exponential form
19.3
Evaluating logarithms without a calculator
19.4
Common logarithms
19.5
Natural log: ln
19.6
Evaluating logarithms using change-of-base formula
19.7
Converting from exponential form to logarithmic form
19.8
Solving exponential equations with logarithms
19.9
Product rule of logarithms