The rate of changedtdP of the number of bears at a national park is modeled by the following differential equation:dtdP=718397280P(1−560P)At t=0, the number of bears at the national park is 199 and is increasing at a rate of 13 bears per day. Find limt→∞P′(t).Answer:
Q. The rate of change dtdP of the number of bears at a national park is modeled by the following differential equation:dtdP=718397280P(1−560P)At t=0, the number of bears at the national park is 199 and is increasing at a rate of 13 bears per day. Find limt→∞P′(t).Answer:
Equilibrium Points Analysis: The given differential equation is:(dtdP)=718397280P(1−560P)This equation models the rate of change of the population of bears in a national park. To find the limit of P′(t) as t approaches infinity, we need to analyze the behavior of the differential equation as P grows large.First, let's look at the equilibrium points of the differential equation, which occur when (dtdP)=0. Setting the right-hand side of the equation to zero gives us:0=718397280P(1−560P)This equation has two solutions for P: P=0 and P=560. These are the points where the population will not change over time.Since we are interested in the limit as t approaches infinity, we need to consider the stability of these equilibrium points. If P=560 is a stable equilibrium, then as t approaches infinity, the population P will approach P′(t)3, and the rate of change P′(t) will approach P′(t)5.
Stability Analysis: To determine the stability of the equilibrium point P=560, we can analyze the sign of the derivative dtdP around this point. If the derivative is negative for P just above 560 and positive for P just below 560, then P=560 is a stable equilibrium.For P slightly less than 560, the term 1−560P is positive, and since P is also positive, the whole expression for dtdP is positive. This means the population is increasing when it is just below 560.For P slightly more than 560, the term 1−560P is negative, and since P is positive, the whole expression for dtdP is negative. This means the population is decreasing when it is just above 560.This behavior indicates that P=560 is indeed a stable equilibrium point.
Approaching Infinity: Since P=560 is a stable equilibrium, as t approaches infinity, the population P will approach 560, and the rate of change P′(t) will approach 0.Therefore, the limit of P′(t) as t approaches infinity is 0.
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