7

Set 2: Exponential Functions

Explanation

Answer: C

The number of subscribers to a newsletter is given by S(w)=50(1.1)wS(w) = 50(1.1)^w, where ww is weeks. How many subscribers are there initially?

A.

1

B.

1.1

C.

50

✓ Correct
D.

55

Detailed Explanation

Choice C is correct. Choice C is the correct answer. The initial value is the coefficient aa. 1. Identify: In y=abxy = ab^x, aa is the starting amount. 2. Locate: a=50a = 50. 3. Verify: At w=0w=0, S(0)=50(1.1)0=50(1)=50S(0) = 50(1.1)^0 = 50(1) = 50. Strategic Tip: Always plug in t=0t=0 or w=0w=0 to find the initial value. Choice B is incorrect because 1.1 is the growth factor. Choice D is incorrect because 55 is the number after 1 week.

Key Steps:

The correct answer is 50

Why others are wrong:
A: Choice A is incorrect and may result from a calculation error.
B: Choice B 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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