How do you use the Change of Base Formula and a calculator to evaluate the logarithm #log_4 20#?

1 Answer
Jul 2, 2015

Answer:

I found: #log_4(20)=2.161#

Explanation:

Your formula can be used to convert, for example, to natural log or #ln#;
you can write:
#log_4(20)=ln(20)/ln(4)=# and both can be evaluated with a pocket calculator giving:
#=2.996/1.386=2.161#
Using this value you can check your result as:

#4^(2.161)=20#