Derivative of ln(ln x) Solution | Step-by-Step Guide

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Homework Statement



Differentiate $$ln(lnx)$$

Homework Equations


The Attempt at a Solution


My solution:
Let $f(x)=lnx$, since${d/dx}ln f(x)={f'(x)/f(x)}$,
${d/dx}ln(lnx)={{1/x}/lnx}/times {1/x}
={1/x^2lnx}$.
 
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Hi Physicsnut! Welcome to PF! :smile:
Physicsnut said:
Let f(x)=lnx, since d/dx ln f(x) = {f'(x)/f(x)},

yes :smile:
{d/dx}ln(lnx) = {{1/x}/lnx}/times {1/x}

nooo :redface:
 
Surround your LaTeX code with either ## or $$. A single $ doesn't work. This is deliberate, because it would have confused people who don't use LaTeX but write stuff about money. LaTeX guide for the forum.
 
##e^x##
$$x^n$$
\int f(x)dx
\frac{df}{dx}

Wow! All this time I have been using "itex" and "tex"!
 
HallsofIvy said:
Wow! All this time I have been using "itex" and "tex"!
The simplified tags have only been available since December 20. :smile:
 
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