Answer:
log(1/100000) = -5
The answer is correct because when we take 10 to the (-5)th power, we get 1/100000
i.e.

Explanation:
We know that log(a) means asks about to what power should we take 10 to get "a" as a result, or, for the equation,

Here, what does x have to be such that 10^x will be equal to a, in log form,

Now, in our case, a = 1/100000
so, the equation is,
x = log(1/100000)
Now, since

So, we see that x = -5 or,
log(1/100000) = -5
The answer is correct because when we take 10 to the (-5)th power, we get 1/100000