Change of Base of Logarithms
logab=logcblogca and logab=1logba
Example 1:
Find the value of the following:
a. log25100
b. log30.45
Answer:
(a) log25100=log10100log1025=log10102log1025=21.3979=1.431(b) log30.45=log100.45log103=−0.34680.4771=−0.727
Example 2
Find the value of the following.
(a) log48
(b) log1255
(c) log8127
(d) log1664


Find the value of the following.
(a) log48
(b) log1255
(c) log8127
(d) log1664

