How do you use the Change of Base Formula and a calculator to evaluate the logarithm #log_4 27#? Precalculus Properties of Logarithmic Functions Functions with Base b 1 Answer Lucy Jul 11, 2018 #log_4 27=log_10 27/log_10 4=2.38# Explanation: #log_a b=log_10b/log_10 a# #log_4 27=log_10 27/log_10 4=2.38# Answer link Related questions What is the exponential form of #log_b 35=3#? What is the product rule of logarithms? What is the quotient rule of logarithms? What is the exponent rule of logarithms? What is #log_b 1#? What are some identity rules for logarithms? What is #log_b b^x#? What is the reciprocal of #log_b a#? What does a logarithmic function look like? How do I graph logarithmic functions on a TI-84? See all questions in Functions with Base b Impact of this question 1157 views around the world You can reuse this answer Creative Commons License