Log in Maths

Last Updated : 24 Jan, 2026

In mathematics, a logarithm is the inverse operation of exponentiation. It is defined as the power to which the base number must be raised to get the given number.

Logarithms serve as mathematical tools that help simplify complex calculations involving exponential relationships.


If you know that bx = y (where b is the base, x is the exponent, and y is the result), it means that you have to raise "b" to the power "x" to obtain the result "y", then by using logarithm we can say that the log of "y" to the base "b" is "x".

This can be written as: log⁡b(y) = x. And it is read as the logarithm of "y" to the base "b".

Example:

  • If 23 = 8, then, log⁡2(8)=3
  • If 51 = 5 then, log5(5) = 1

Also, logarithm of 1 in any base is always 0 as a0 = 1 or loga1 = 0(for a > 0).

Note : If the number is same as the base then the its log value will always be equal to one.

For Beginners

This section introduces the basics of logarithms, their rules, properties, formulas, and how to use log and antilog tables.

Practice Questions

Practice and test your understanding of logarithms with quizzes, MCQs, and problem-solving exercises.

For Aptitude Preparation

Prepare for competitive exams with commonly asked aptitude questions on logarithms along with quick-solving tips and tricks.

For Programmers

Learn how logarithms are used in programming, especially in time complexity and coding problems, with examples in Python.

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