2

Set 14: Exponential Functions (Advanced)

Explanation

Answer: A

What is the horizontal asymptote of the function f(x)=5(2)x+3f(x) = 5(2)^x + 3?

A.

y=3y = 3

✓ Correct
B.

y=5y = 5

C.

y=0y = 0

D.

y=2y = 2

Detailed Explanation

Choice A is correct. Choice A is the correct answer. The horizontal asymptote is determined by the constant term. 1. Standard Form: f(x)=abx+kf(x) = ab^x + k, where kk is the vertical shift. 2. Asymptote: As xx \to -\infty, (2)x0(2)^x \to 0, so f(x)0+3=3f(x) \to 0 + 3 = 3. 3. Conclusion: The horizontal asymptote is y=3y = 3. Strategic Tip: The constant added/subtracted shifts the asymptote from y=0y=0 to y=ky=k. Choice B is incorrect because 5 is the coefficient aa, not the asymptote. Choice C is incorrect because this would be true only if there were no constant term. Choice D is incorrect because 2 is the base, not related to the asymptote.

Key Steps:

The correct answer is y=3y = 3

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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