The rate of changedtdP of the number of bacteria in a tank is modeled by the following differential equation:dtdP=98492P(598−P)At t=0, the number of bacteria in the tank is 196 and is increasing at a rate of 16 bacteria per minute. At what value of P does the graph of P(t) have an inflection point?Answer:
Q. The rate of change dtdP of the number of bacteria in a tank is modeled by the following differential equation:dtdP=98492P(598−P)At t=0, the number of bacteria in the tank is 196 and is increasing at a rate of 16 bacteria per minute. At what value of P does the graph of P(t) have an inflection point?Answer:
Find First Derivative: To find the inflection point, we need to find the second derivative of P with respect to t and set it equal to zero. The second derivative will tell us where the concavity of the graph changes, which is the inflection point.First, let's find the first derivative, which is given by the differential equation:dtdP=98492P(598−P)
Find Second Derivative: Now, we need to find the second derivative dt2d2P. To do this, we will differentiate dtdP with respect to P and then multiply by dtdP again due to the chain rule.dt2d2P=dPd(dtdP)×dtdP
Differentiate First Derivative: Differentiating dtdP with respect to P gives us: dPd(98492P(598−P))=98492(598−2P)
Multiply Derivatives: Now, we multiply this derivative by (dtdP) to get the second derivative with respect to time: (dt2d2P)=(98492)(598−2P)×(98492)P(598−P)
Set Second Derivative Equal to Zero: To find the inflection point, we set the second derivative equal to zero and solve for P:0=(98492)(598−2P)∗(98492)P(598−P)
Simplify Equation: We can simplify the equation by setting the factors equal to zero:598−2P=0 or P(598−P)=0
Solve for P: Solving the first equation for P gives us:2P=598P=299
Disregard Endpoints: Solving the second equation for P gives us two solutions:P=0 or 598−P=0P=0 or P=598
Identify Inflection Point: However, since we are looking for the inflection point where P is changing, we disregard the solutions P=0 and P=598 because they represent the endpoints of the interval where the population exists. The inflection point occurs at P=299.
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