LHS: because alnx = lnxa, 2ln2x = ln(2x)2 = ln4x2
Now, because ln and e are inverse functions, we take both sides to the power of e. Therefore:
eln4x^2 = e1 + ln3
4x2 = e1 + ln3
x2 = (e1 + ln3) / 4
x = sq root of [(e1 + ln3) / 4]
entering into the calculator, this gives us +/- 1.43