The rate of changedtdP of the number of algae in a tank is modeled by the following differential equation:dtdP=106142317P(1−662P)At t=0, the number of algae in the tank is 174 and is increasing at a rate of 28 algae per minute. At what value of P is P(t) growing the fastest?Answer:
Q. The rate of change dtdP of the number of algae in a tank is modeled by the following differential equation:dtdP=106142317P(1−662P)At t=0, the number of algae in the tank is 174 and is increasing at a rate of 28 algae per minute. At what value of P is P(t) growing the fastest?Answer:
Simplify Equation: The growth rate of P(t) is given by the differential equation dtdP=106142317P(1−662P). To find the value of P where P(t) is growing the fastest, we need to find the maximum point of the growth rate function. This occurs where the derivative of the growth rate with respect to P is zero. Let's first simplify the growth rate function.
Find Derivative: Simplify the differential equation by dividing the constant 2317 by 10614 to get a simplified constant factor.106142317≈0.2183 (rounded to four decimal places for simplicity).So, the simplified differential equation is dtdP≈0.2183P(1−662P).
Set Derivative Equal: Now, let's find the derivative of the growth rate function with respect to P, which is dPd[dtdP]. This will give us the rate of change of the growth rate with respect to P. The derivative of 0.2183P(1−662P) with respect to P is 0.2183(1−662P)−0.2183P(6621)=0.2183−6620.2183×2P.
Eliminate Denominator: Set the derivative equal to zero to find the critical points:0=0.2183−6620.2183×2P.This simplifies to 0=2183−6622183×2P.
Solve for P: Multiply both sides by 662 to eliminate the denominator:0=2183×662−2183×2P.
Confirm Maximum: Divide both sides by 2183 to solve for P: 0=662−2P.
Confirm Maximum: Divide both sides by 2183 to solve for P: 0=662−2P. Now, solve for P: 2P=662. P = rac{662}{2}. P=331.
Confirm Maximum: Divide both sides by 2183 to solve for P: 0=662−2P. Now, solve for P: 2P=662. P = rac{662}{2}. P=331. We found that the critical point is at P=331. To confirm that this is a maximum, we can use the second derivative test or analyze the behavior of the growth rate function. However, since the growth rate function is a parabola that opens downwards (as the coefficient of P2 is negative), we can conclude that P=331 is the maximum point without further calculation.
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