How do you write #10^3 = 1000# in log form? Precalculus Properties of Logarithmic Functions Logarithm-- Inverse of an Exponential Function 1 Answer Trevor Ryan. Mar 25, 2016 #log_10 1000=3# or simply #log1000=3# Explanation: This follows directly from the definition : #y=log_a x iff a^y=x# Answer link Related questions What is a logarithm? What are common mistakes students make with logarithms? How can a logarithmic equation be solved by graphing? How can I calculate a logarithm without a calculator? How can logarithms be used to solve exponential equations? How do logarithmic functions work? What is the logarithm of a negative number? What is the logarithm of zero? How do I find the logarithm #log_(1/4) 1/64#? How do I find the logarithm #log_(2/3)(8/27)#? See all questions in Logarithm-- Inverse of an Exponential Function Impact of this question 16806 views around the world You can reuse this answer Creative Commons License