I am given the function f(x) = ln(lnx^2) to differentiate; but I am not entirely certain how to do this. Could someone possibly help me?

Thank you

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- Apr 24th 2012, 12:37 PMBashyboyDerivative Of A Natural Logarithm
I am given the function f(x) = ln(lnx^2) to differentiate; but I am not entirely certain how to do this. Could someone possibly help me?

Thank you - Apr 24th 2012, 01:24 PMPlatoRe: Derivative Of A Natural Logarithm
- Apr 24th 2012, 02:27 PMHallsofIvyRe: Derivative Of A Natural Logarithm
You need to know this: the derivative of f(x)= ln(u(x)) is [tex]\frac{1}{u}\frac{du}{dx}[/itex].

As Plato said, $\displaystyle ln(ln(x^2)= ln(2ln(x))= ln(ln(x))+ ln(2)$. "ln(2)" is a constant and its derivative is 0.

so you have ln(u(x)) with u(x)= ln(x).