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Logarithm Calculator Online Tool |
Logarithm Calculator: Compute Logs with Our Free Online Tool
Our free logarithm calculator helps you quickly compute logarithmic values with any valid base. Perfect for students, engineers, and math enthusiasts who need accurate log calculations.
Understanding Logarithms
Logarithms are the inverse operations of exponentiation. The logarithm of a number to a given base is the exponent to which the base must be raised to produce that number. For example, log₁₀(100) = 2 because 10² = 100.
Common Logarithmic Bases
- Common Logarithm (Base 10): Written as log₁₀(x) or simply log(x)
- Natural Logarithm (Base e): Written as logₑ(x) or ln(x), where e ≈ 2.71828
- Binary Logarithm (Base 2): Written as log₂(x), commonly used in computer science
Logarithmic Properties
Logarithms have several important properties that make them useful in calculations:
- Product Rule: logₐ(mn) = logₐ(m) + logₐ(n)
- Quotient Rule: logₐ(m/n) = logₐ(m) - logₐ(n)
- Power Rule: logₐ(mⁿ) = n·logₐ(m)
- Change of Base: logₐ(b) = logₓ(b) / logₓ(a)
Applications of Logarithms
Logarithms are used in various fields including:
- Science: Measuring pH, sound intensity (decibels), and earthquake magnitude
- Finance: Calculating compound interest and investment growth
- Computer Science: Analyzing algorithm complexity
- Mathematics: Solving exponential equations
Frequently Asked Questions About Logarithms
What is the logarithm of zero?
The logarithm of zero is undefined for any base, as no number raised to any power equals zero.
What is the logarithm of a negative number?
Logarithms of negative numbers are undefined in the real number system, but can be represented using complex numbers.
What is the value of log(1)?
The logarithm of 1 is always 0 for any valid base, because any number raised to the power of 0 equals 1.
How do you calculate logarithms with different bases?
You can use the change of base formula: logₐ(b) = logₓ(b) / logₓ(a), where x can be any positive number (commonly 10 or e).