6

Set 9: Exponential Functions (Advanced)

Explanation

Answer: A

A streaming service grows from 1 million to 16 million subscribers in 4 years. What is the annual growth factor?

A.

2

✓ Correct
B.

4

C.

16

D.

8

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Find the annual growth factor. 1. Formula: S(t)=S0(b)tS(t) = S_0(b)^t where S0=1S_0 = 1, S(4)=16S(4) = 16. 2. Solve: 16=1(b)416= 1(b)^4, so b4=16b^4 = 16. 3. Calculate: b=164=2b = \sqrt[4]{16} = 2. 4. Verify: 1(2)4=161(2)^4 = 16 ✓ Strategic Tip: To find bb from b4=16b^4 = 16, take the 4 th root. Choice B is incorrect because this would give (4)4=256(4)^4 = 256. Choice C is incorrect because this is the total growth, not annual factor. Choice D is incorrect because this doesn't match b4=16b^4 = 16.

Key Steps:

The correct answer is 2

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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