Step by step
The question
Question: work out log 1000.
A log with no small number is base 10.
log 1000
So it is log base 10.
log = log10
1 What the log asks
A log is a power.
log 1000 asks: 10 to what power is 1000?
a log is a power
10 to the power what is 1000?
10? = 1000
2 Find the power
10 times 10 times 10 is 1000.
That is 3 10's.
10 × 10 × 10 = 1000
So the power is 3.
103 = 1000
So log 1000 = 3.
log 1000 = 3
Let's look back.
First: what the log asks.
Last: find the power.
Answer
log 1000 = 3