Table of contents
- 0. Functions7h 52m
- Introduction to Functions16m
- Piecewise Functions10m
- Properties of Functions9m
- Common Functions1h 8m
- Transformations5m
- Combining Functions27m
- Exponent rules32m
- Exponential Functions28m
- Logarithmic Functions24m
- Properties of Logarithms34m
- Exponential & Logarithmic Equations35m
- Introduction to Trigonometric Functions38m
- Graphs of Trigonometric Functions44m
- Trigonometric Identities47m
- Inverse Trigonometric Functions48m
- 1. Limits and Continuity2h 2m
- 2. Intro to Derivatives1h 33m
- 3. Techniques of Differentiation3h 18m
- 4. Applications of Derivatives2h 38m
- 5. Graphical Applications of Derivatives6h 2m
- 6. Derivatives of Inverse, Exponential, & Logarithmic Functions2h 37m
- 7. Antiderivatives & Indefinite Integrals1h 26m
- 8. Definite Integrals3h 25m
2. Intro to Derivatives
Tangent Lines and Derivatives
Problem 97
Textbook Question
97–100. Logistic growth Scientists often use the logistic growth function P(t) = P₀K / P₀+(K−P₀)e^−r₀t to model population growth, where P₀ is the initial population at time t=0, K is the carrying capacity, and r₀ is the base growth rate. The carrying capacity is a theoretical upper bound on the total population that the surrounding environment can support. The figure shows the sigmoid (S-shaped) curve associated with a typical logistic model. <IMAGE>
{Use of Tech} Gone fishing When a reservoir is created by a new dam, 50 fish are introduced into the reservoir, which has an estimated carrying capacity of 8000 fish. A logistic model of the fish population is P(t) = 400,000 / 50+7950e^−0.5t, where t is measured in years.
a. Graph P using a graphing utility. Experiment with different windows until you produce an S-shaped curve characteristic of the logistic model. What window works well for this function?
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1
Identify the parameters in the logistic growth function P(t) = 400,000 / (50 + 7950e^(-0.5t)), where P₀ = 50, K = 8000, and r₀ = 0.5.
Set up a graphing utility, such as Desmos or a graphing calculator, to input the logistic function P(t).
Choose an appropriate window for the graph. A good starting point for the x-axis (time t) could be from 0 to 20 years, and for the y-axis (population P), from 0 to 8000 fish, since this is the carrying capacity.
Plot the function and observe the shape of the curve. Adjust the window settings if necessary to better visualize the S-shaped curve characteristic of logistic growth.
Experiment with different values for the x-axis and y-axis limits to find the best view of the curve, ensuring that the population approaches the carrying capacity as time increases.
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