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Mathematics

What is Logarithms?

A logarithm answers the question 'what power do I raise this base to, to get this number?' It's the inverse of exponentiation, and it turns multiplication into addition — making huge ranges of numbers manageable.

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Key things to understand

  • 1log base b of x = the exponent you raise b to, to get x (e.g., log₁₀ 1000 = 3).
  • 2It's the inverse of raising a number to a power.
  • 3It compresses huge scales (used in pH, decibels, the Richter scale).
  • 4It turns multiplication into addition, which simplified pre-calculator math.

Frequently asked questions

What is a logarithm in simple terms?
The power you must raise a base number to in order to get another number.
Where are logarithms used?
Measuring earthquakes (Richter), sound (decibels), acidity (pH), and in algorithms and growth rates.
What is a natural logarithm?
A logarithm with base e (≈2.718), common in math and science for continuous growth.

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