47. \[ \lim_{x \to \infty} \left( e^x + x \right)^{\frac{1}{x}} \]






Answer is: option1

\( e \)

Solution:

Define:

\[ L = \lim_{x \to \infty} \left( e^x + x \right)^{\frac{1}{x}} \]

Taking the natural logarithm:

\[ \ln L = \lim_{x \to \infty} \frac{1}{x} \ln (e^x + x) \]

For large \( x \), the term \( e^x \) dominates over \( x \), so we approximate:

\[ e^x + x \approx e^x \]

Taking the logarithm:

\[ \ln(e^x + x) \approx \ln e^x = x \]

Thus:

\[ \ln L = \lim_{x \to \infty} \frac{1}{x} \cdot x = 1 \]

Since \( \ln L = 1 \), we exponentiate both sides:

\[ L = e^1 = e \]

Correct Answer: \( e \)

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