How do you solve $ln x + ln 3x = 12$ ?

Question

3734 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-12-06T14:58:20

$x = + sqrt(3)/3 e^6$

$ln (x * 3x) = 12$

$x * 3x = e^12$

$x^2 = 1/3 e^12$

$x = ± sqrt(3)/3 e^6$

But x > 0.

How do you solve ln x + ln 3x = 12ln x + ln 3x = 12?