2

Set 4: Exponential Functions (Intermediate)

Explanation

Answer: A

Which is equivalent to 272x27^{2x}?

A.

36x3^{6x}

✓ Correct
B.

93x9^{3x}

C.

33x3^{3x}

D.

81x81^x

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Rewrite with base 3. 1. Rewrite: 27=3327= 3^3, so 272x=(33)2x27^{2 x} = (3^3)^{2 x}. 2. Power rule: (am)n=amn(a^m)^n = a^{mn}, so (33)2x=36x(3^3)^{2 x} = 3^{6 x}. 3. Verify Choice B: 93x=(32)3x=36x9^{3 x} = (3^2)^{3 x} = 3^{6 x} ✓ (Also equivalent!) Strategic Tip: Multiple representations can be correct—check all options. Choice C is incorrect because 33x=(33)x=27x272x3^{3 x} = (3^3)^x = 27^x \neq 27^{2 x}. Choice D is incorrect because 81x=(34)x=34x36x81^x = (3^4)^x = 3^{4 x} \neq 3^{6 x}.

Key Steps:

The correct answer is 36x3^{6x}

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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