How do you evaluate log_5(1/2)?

1 Answer
May 2, 2016

By calculator -0.431 (3 dec places)

Explanation:

Let log_5 (1/2) = x

Change from log form to index from: 5^x = 1/2

Now, because the variable is the index, and 1/2 is not an exact power of 5, we need to use logs.

Power law: x log5 = log 0.5)

x = (log0.5)/(log5)

From a calculator x = -0.431