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Module 3: Applications of First-Order ODEs

See first-order differential equations in action through real-world models: exponential growth and decay, population dynamics, mixing tanks, and Newton's law of cooling.

4 Lessons
~4-5 hours
10 Practice Problems
Module Quiz

Your Progress

Lessons 1-4
Practice
Module Quiz
Review

Learning Objectives

By the end of this module, you will be able to:

  • Model exponential growth and decay with dP/dt = kP and find half-life or doubling time
  • Analyze the logistic equation dP/dt = rP(1 - P/K) including equilibria and carrying capacity
  • Set up mixing problems using rate-in minus rate-out and solve the resulting linear ODE
  • Apply Newton's law of cooling dT/dt = k(T - T_env) to forensic and practical problems
  • Translate word problems into differential equations and interpret solutions in context

Module Lessons

1

Exponential Growth and Decay

Model populations, radioactive decay, and compound interest with dP/dt = kP. Learn half-life and doubling time.

35-45 minutes

2

Population Models: The Logistic Equation

Go beyond exponential growth with the logistic model, carrying capacity, equilibria, and harvesting.

35-45 minutes

3

Mixing Problems

Set up and solve ODEs for tanks with inflow and outflow of solutions. Master the rate-in minus rate-out framework.

30-40 minutes

4

Newton's Law of Cooling

Model temperature change with dT/dt = k(T - T_env). Apply to forensics, cooking, and engineering.

30-40 minutes

After the Lessons

Practice Problems

Apply what you learned with 10 problems covering growth/decay, logistic models, mixing, and cooling.

Practice Problems

Module Quiz

Test your understanding with a 10-question quiz. Detailed solutions included!

Take Module Quiz

Study Materials

Printable study guide and quick reference card for exam prep.

Begin Module 3 →