Question

Differentiate: $\log \left(\log x\right),x>1$

Answer 1

We'll apply chain rule to find the differentiation

$\log x=t$

$\frac{d}{dx}\log t=\frac{1}{t}\frac{dt}{dx}=\frac{1}{t}\frac{d\left(logx\right)}{dx}=\frac{1}{t}\times \frac{1}{x}=\frac{1}{xlogx}$