Rewrite log(1/10000)=-4 in exponential form.

y=log_{a}x and x=a^{y }are
equivalent. Also, when there is no base specifically written, we can assume
that log is base 10 (also called the common logarithmic function, denoted as
simply log).

Therefore, -4=log_{(10)}(1/10000) and
1/10000=10^{-4} are equivalent.