show this limits
$$\lim_{x\to 0^{+}}\dfrac{x\cdot\dfrac{\log{x}}{\log{(1-x)}}}{\log{\left(\dfrac{\log{x}}{\log{(1-x)}}\right)}}=1$$
I fell this limits not easy to show it.
since
$$\log{(1-x)}=-x+o(x^2)\Longrightarrow x\cdot\dfrac{\log{x}}{\log{(1-x)}}\approx -\log{x}+o(\log{x})$$
and I know
$$\dfrac{\log{x}}{\log{(1-x)}}\to +\infty$$
then I don't know How to deal this problem
This Problem is from Analysis problem book exercise (MIn hui xie)
Answer
As $x\to 0^+$ we have
$$
\frac{\log x}{\log(1-x)}\sim -\frac{\log x}{x}=\frac{1}{x}\log\left(\frac{1}{x} \right)
$$
and then
$$
\frac{x\cdot\frac{\log{x}}{\log{(1-x)}}}{\log{\left(\frac{\log{x}}{\log{(1-x)}}\right)}}\sim \frac{\log(\frac{1}{x})}{\log\left(\frac{1}{x}\log(\frac{1}{x})\right)}
$$
Changing $u=\frac{1}{x}$, we have using de l'Hopital's rule
$$
\lim_{u\to\infty}\frac{\log u}{\log(u\log u)}=\lim_{u\to\infty}\frac{\log u}{\log u +1}=1.
$$
So your limit is
$$\lim_{x\to 0^{+}}\dfrac{x\cdot\dfrac{\log{x}}{\log{(1-x)}}}{\log{\left(\dfrac{\log{x}}{\log{(1-x)}}\right)}}=1.$$
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