How do you simplify #ln (1/e^3)#? Precalculus Exponential and Logistic Functions The Natural Base e 1 Answer Bill K. Dec 3, 2015 #ln(1/e^(3))=ln(e^(-3))=-3#. Explanation: Since #ln(x)# and #e^{x}# are inverse functions, #ln(e^{x})=x# for all values of #x#. Since #1/e^{3}=e^{-3}# by definition of negative exponents, it follows that #ln(1/e^(3))=ln(e^(-3))=-3#. You could also note that #ln(1/e^{3})=ln(1)-ln(e^{3})=0-3=-3# since #ln(A/B)=ln(A)-ln(B)# and #ln(1)=0#. Answer link Related questions What is base e? What are common mistakes students make with base e? What is the value of e? What is Euler's number? What is the significance of Euler's number? What does Euler's number represent? How do I work with Euler's number in Excel? How do I find the inverse of #e^x#? How does e relate to #pi#? Is the number e rational or irrational? See all questions in The Natural Base e Impact of this question 14803 views around the world You can reuse this answer Creative Commons License