What is x if Ln9+ln4x^2=2?

1 Answer
May 4, 2018

We wish to find x if ln9 + ln(4x^2) = 2. We will need to use some log rules here. Specifically, recall that:

lnx + lny = ln(xy)
e^(ln(x)) = x

Using the above two rules, we can quickly come to an answer.

ln 9 + ln(4x^2) = 2 (Use Rule 1 to combine.)
ln(9*4x^2) = 2
ln(36x^2) = 2 (Use Rule 2 and exponentiate both sides.)
36x^2 = e^2
x^2 = e^2/(36) = (e/6)^2
x = pm e/6