2

Set 5: Exponential Functions

Explanation

Answer: A

If e2x=50e^{2x} = 50, what is exe^x?

A.

507.07\sqrt{50} \approx 7.07

✓ Correct
B.

2525

C.

100100

D.

5050

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use properties of exponents. 1. Given: e2x=50e^{2 x} = 50. 2. Rewrite: e2x=(ex)2=50e^{2 x} = (e^x)^2 = 50. 3. Solve: ex=50=25×2=527.07e^x = \sqrt{50} = \sqrt{25 \times 2} = 5\sqrt{2} \approx 7.07. Strategic Tip: (am)n=amn(a^m)^n = a^{mn}, so e2x=(ex)2e^{2 x} = (e^x)^2. Choice B is incorrect because (ex)2=50(e^x)^2 = 50, not ex=25e^x = 25. Choice C is incorrect because this would give e2x=10000e^{2 x} = 10000. Choice D is incorrect because exe2xe^x \neq e^{2 x}.

Key Steps:

The correct answer is 507.07\sqrt{50} \approx 7.07

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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