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Logarithm Calculator

Logarithm Formula:

\[ \log_b(x) = \frac{\ln(x)}{\ln(b)} \]

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1. What is a Logarithm?

A logarithm is the inverse operation to exponentiation, just as division is the inverse of multiplication. The logarithm of a number x with respect to base b is the exponent to which b must be raised to yield x.

2. How Does the Calculator Work?

The calculator uses the change of base formula:

\[ \log_b(x) = \frac{\ln(x)}{\ln(b)} \]

Where:

Explanation: This formula allows calculation of logarithms with any base using natural logarithms.

3. Common Logarithm Bases

Details:

4. Using the Calculator

Tips: Enter positive numbers for both x and the base. The result is unitless. For natural logarithms, set base to 2.71828 (e).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between log and ln?
A: log typically means log10 (common logarithm) while ln means loge (natural logarithm).

Q2: Can I calculate logarithms with base 1?
A: No, base must be a positive number different from 1.

Q3: What is logb(1) for any base?
A: Always 0, because b0 = 1 for any valid base b.

Q4: What is logb(b)?
A: Always 1, because b1 = b.

Q5: How are logarithms used in real life?
A: Used in many fields including science (pH scale), finance (compound interest), and computer science (algorithm complexity).

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