Logarithm Calculator
log_b(a) is the exponent you put on b to get a. Common log is base 10; natural log is base e.
A logarithm answers: to what power must the base be raised to obtain this number?
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Example problems
How this solver works
- Identify the base.
- Evaluate with the numeric engine.
- Use log identities only when they apply exactly.
Formula
Definition of logarithm.
Worked examples
log(100)
- 10^2 = 100
- log10(100)=2
Answer: 2
Common mistakes
log(a+b) ≠ log a + log b
The sum rule is log(ab) = log a + log b.
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Frequently asked questions
What is ln?
ln means log base e, the natural logarithm.