How do you simplify ln 3 − 2 ln 9 + ln 18 ? Precalculus Properties of Logarithmic Functions Natural Logs 1 Answer George C. Sep 1, 2015 ln 3 - 2 ln 9 + ln 18 = ln (2/3) = ln 2 - ln 3 Explanation: Use:color(white)(XX)ln a + ln b = ln (ab) and:color(white)(XX)ln a - ln b = ln (a/b) to simplify: ln 3 - 2 ln 9 + ln 18 =ln 3 + ln 18 - ln 9^2 =ln (3*18) - ln 81 =ln 54 - ln 81 =ln (54/81) =ln (2/3) =ln 2 - ln 3 Answer link Related questions What is the natural log of e? What is the natural log of 2? How do I do natural logs on a TI-83? How do I find the natural log of a fraction? What is the natural log of 1? What is the natural log of infinity? Can I find the natural log of a negative number? How do I find a natural log without a calculator? How do I find the natural log of a given number by using a calculator? How do I do natural logs on a TI-84? See all questions in Natural Logs Impact of this question 8714 views around the world You can reuse this answer Creative Commons License