4

Set 16: Exponential Functions (Intermediate)

Explanation

Answer: B

Consider the exponential function y=150(1.04)xy = 150(1.04)^x. What is the initial value of this function?

A.

1.04

B.

150

✓ Correct
C.

4

D.

156

Detailed Explanation

Choice B is correct. Choice B is the correct answer. The initial value corresponds to aa in the standard form y=abxy = ab^x. 1. Identify: The standard form of an exponential function is y=abxy = ab^x, where aa is the initial value (y-intercept) and bb is the growth/decay factor. 2. Compare: In the given equation y=150(1.04)xy = 150(1.04)^x, the coefficient aa is 150. 3. Conclude: Therefore, the initial value is 150. Strategic Tip: The initial value is always the number multiplying the power term. It represents the starting amount when x=0x=0. Choice A is incorrect because 1.04 is the growth factor bb, not the initial value. Choice C is incorrect because 4 represents the percentage growth rate (4%), not the initial value. Choice D is incorrect because 156 is the value when x=1x=1 (150×1.04150\times 1.04), not the initial value.

Key Steps:

The correct answer is 150

Why others are wrong:
A: Choice A 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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