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Set 8: Exponential Functions

Explanation

Answer: A

A population follows logistic growth: P(t)=10001+9e0.5tP(t) = \frac{1000}{1 + 9e^{-0.5t}}. What is the carrying capacity?

Logistic vs Exponential Growth

A.

1,000

✓ Correct
B.

9

C.

100

D.

500

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Identify the limiting value. 1. Logistic form: P(t)=K1+AertP(t) = \frac{K}{1 + Ae^{-rt}} where KK is carrying capacity. 2. As tt \to \infty: e0.5t0e^{-0.5 t} \to 0, so P(t)10001+0=1000P(t) \to \frac{1000}{1 + 0} = 1000. 3. Carrying capacity: The maximum population is 1,000. Strategic Tip: In logistic growth, the numerator is always the carrying capacity. Choice B is incorrect because 9 is the coefficient AA, not the limit. Choice C is incorrect because this is the initial population P(0)=100010=100P(0) = \frac{1000}{10} = 100. Choice D is incorrect because this is half the carrying capacity.

Key Steps:

The correct answer is 1,000

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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