What does log in algebra mean?

Answer 1

The log or logarithm is the power to which ten needs to be raised to equal a number. Log 10=1 because 10^1=10

Log 100=2 because 10^2=100

Sometimes we use different bases. Like base 2. Then it is what 2 is raised by to get the number.

Log "base 2" 8=3 because 2^3=8