I need help with this problem.

find the derivative of f(u) = ln(u)/1 + ln(2u)

I started by finding ln of ln(u) and 1 + ln(2u) . . .

I got ln(u) = 1/u and 1 + ln(2u) = 1. Then I just used the quotient rule, but I can't get the right answer. The answer is supposed to be 1 + ln2/ u[1 + ln(2u)]^2.