# Using math.log or math.log10

Hey! I am currently working on a project where I have to use logarithms. I didn’t study them at school yet and would like to know how these work. Do you have any videos/documents that can explain how to use them and what they do? Thanks!

A logarithm is the inverse of a power. You’ll always find logarithms with this pattern: log(x).
Logarithms are essentially finding the amount of times X has been powered to by its base (aka exponent).
A logarithm has a base, this is, the base number (2^3), and X (the result from the power, in this case, 8.) The base number is written below log, and if not declared, it’s usually the e number, or 10.
Now, we won’t go in how to calculate logarithms, but essentially:

• If 2^3 = 8, then the logarithm will be represented as log2(8) = 3.

In Lua, math.log takes its base as e, the irrational number 2.78. math.log10 is essentially a logarithm with base 10.
For example:

function a()
return math.log10(100)
end

local b = a() -- 2, as 10^2 = 100

In short, it’s the inverse of a power.
Well sorry if other programmers see this horrid explanation, I didn’t study this in English.