第216题 | 知识点:强化极限训练(六)
题目
$$
\text{求极限 } \lim_{x\to0}\frac{(1+x)^{\frac{2}{x}} - e^2[1 - \ln(1+x)]}{x}
$$
解答
$$
\begin{aligned}
\lim_{x\to0}\frac{(1+x)^{\frac{2}{x}} - e^2[1 - \ln(1+x)]}{x}
&=
\lim_{x\to0}\frac{e^{\frac{2\ln(1 + x)}{x}} - e^2[1 - \ln(1+x)]}{x}
\\
&=
e^2 \cdot \lim_{x\to0}\frac{e^{\frac{2\ln(1 + x) - 2x}{x}} - 1 + \ln(1+x)}{x}
\\
&=
e^2 \cdot \lim_{x\to0}\frac{e^{\frac{2\ln(1 + x) - 2x}{x}} - 1}{x} +
e^2 \cdot \lim_{x\to0}\frac{\ln(1+x)}{x}
\\
&=
e^2 \cdot \lim_{x\to0}\frac{2\ln(1 + x) - 2x}{x^2} +
e^2
\\
&=
-e^2 +
e^2
\\
&= 0
\end{aligned}
$$
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