Question

What is the derivative of `f(x)=ln(lnx)`?

Answer 1

I found: `f'(x)=1/(xln(x))`

Explanation:

Here you can use the Chain Rule deriving the first `ln` as it is (red) leaving its argument untouched and then multiply times the derivative of the second inside the first (blue):
`f'(x)=color(red)(1/ln(x))*color(blue)(1/x)=1/(xln(x))`