1

Set 3: Exponential Functions (Intermediate)

Explanation

Answer: A

If ln(x)=2\ln(x) = 2, what is xx?

A.

e27.39e^2 \approx 7.39

✓ Correct
B.

22

C.

1e2\frac{1}{e^2}

D.

e2.718e \approx 2.718

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use the definition of natural logarithm. 1. Definition: ln(x)=y\ln(x) = y means ey=xe^y = x. 2. Apply: ln(x)=2\ln(x) = 2 means x=e2x = e^2. 3. Calculate: e27.389e^2 \approx 7.389. Strategic Tip: ln\ln and exe^x are inverse functions: eln(x)=xe^{\ln(x)} = x and ln(ex)=x\ln(e^x) = x. Choice B is incorrect because this confuses the input and output. Choice C is incorrect because this inverts incorrectly. Choice D is incorrect because this is e1e^1, not e2e^2.

Key Steps:

The correct answer is e27.39e^2 \approx 7.39

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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