4

Set 8: Exponential Functions (Intermediate)

Explanation

Answer: A

The function f(x)=50(1.2)xf(x) = 50(1.2)^x is graphed. What happens to yy as xx increases?

A.

yy increases without bound

✓ Correct
B.

yy approaches zero

C.

yy approaches 50

D.

yy remains constant at 1.2

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Analyze the behavior as xx \to \infty. 1. Base: b=1.2>1b = 1.2 > 1 means exponential growth. 2. Behavior: As xx increases, (1.2)x(1.2)^x grows larger and larger. 3. Conclusion: y=50(1.2)xy = 50(1.2)^x increases without bound. Strategic Tip: For exponential growth (b>1b > 1), the function grows indefinitely as xx increases. Choice B is incorrect because this describes decay (b<1b < 1), not growth. Choice C is incorrect because 50 is the initial value, not a limiting value. Choice D is incorrect because yy is not constant; it grows exponentially.

Key Steps:

The correct answer is yy increases without bound

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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