The inverse of the function f(x) = bˣ is the logarithmic function with base b, denoted as

The inverse of the function f(x) = is the logarithmic function with base b, denoted as
. This means that for any value y, f(y) is the value x such that f(x) = y. In other words, if f(x) = , then f(y) = x when = y.
To see why this is true, consider the following equation:
= y
Taking the logarithm of both sides with base b, we get:

Since
= x, we have:

Therefore, f(y) =
