Question

Find the derivative ln(ln7x) using chain rule

Answer 1

First let \(u = \ln(7x)\)
So we want to find \[
\frac{d}{dx} \ln(\ln(7x))= \frac{d}{dx}\ln(u) = \frac{d}{du}[\ln(u)]\frac{du}{dx} = \frac{1}{u}\frac{du}{dx}
\]

Answer 2

I'd say use the chain-rule, obviously =)

Answer 3

Thank you, Wio

Answer 4

@jwallen Well, that was enough to get you started. It wasn't the complete answer. I hope you figured the rest out on your own though.

Answer 5

I think i plug in u in du/dx=1/u du/dx