How do you use the Change of Base Formula and a calculator to evaluate the logarithm #log_6 120#?

1 Answer
Aug 11, 2015

Some scientific calculators allow you to choose the base of the logarithm. However, if this is not the case, then the log function needs to be represented in terms of either base #10# or base #e#.

# log_a b = log_c b/log_c a #

Hence: # log_6 120 = log_10 120/log_10 6 = ln 120/ln 6 #
where # ln # is the natural logarithm i.e. # log_e #