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Logistic曲线 P(t) = K/(1 + e^(-rt)) 。证明在 P = K/2 (承载能力的一半)处有拐点。
Logistic曲线 P(t) = K/(1 + e^(-rt)) 。证明在 P = K/2 (承载能力的一半)处有拐点。
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