1.2 Basic Concepts
We define ordinary differential equations and what it means for a function to be a
solution to such an equation.
1.1 Applications Leading to Differential Equations
We discuss population growth, Newton’s law of cooling, glucose absorption, and
spread of epidemics as phenomena that can be modeled with differential
equations.
2.1 Linear First-Order Differential Equations
We develop a technique for solving first-order linear differential equations.
1.3 Direction Fields for First Order Equations
We explore direction fields (also called slope fields) for some examples of first order
differential equations.
2.2 Separable Equations
We define what it means for a first order equation to be separable, and we work out
solutions to a few examples of separable equations.
2.3 Existence and Uniqueness of Solutions of Nonlinear Equations
We study an existence and uniqueness theorem for a first-order initial value
problem. We do not attempt the proof, as it is beyond the scope of this
book.
2.5 Exact Equations
We learn how to recognize whether or not a first-order equation is exact. We also
learn how to solve an exact equation.
2.4A Bernoulli’s Equations
We show how multiplying an equation by an integrating factor can make the equation
exact, and we give examples where this is a nice technique for solving a first-order
equation.
2.6 Integrating Factors
We show how multiplying an equation by an integrating factor can make the equation
exact, and we give examples where this is a nice technique for solving a first-order
equation.
3.2 The Improved Euler Method and Related Methods
We explore some ways to improve upon Euler’s method for approximating the
solution of a differential equation.
3.3 Runge-Kutta Method
We study a fourth order method known as Runge-Kutta which is more accurate than
any of the other methods studied in this chapter.
4.1 Exponential Growth and Decay
We solve a separable differential equation and describe a few of its many
applications.
4.2A Newton’s Law of Cooling
We study Newton’s Law of Cooling as an application of a first order separable
differential equation.
4.3 Elementary Mechanics
We study several applications of first order differential equations to elementary
mechanics.
4.4 Autonomous Second Order Equations
We define autonomous equations, explain how autonomous second order equations
can be reduced to first order equations, and give several applications.
4.5 Applications to Curves
We study a number of ways that families of curves can be defined using differential
equations.
5.1 Homogeneous Linear Equations
We develop a technique for solving homogeneous linear differential equations.
5.2 Constant Coefficient Homogeneous Equations
We examine the various possibilities for types of solutions when solving constant
coefficient homogeneous equations.
5.4 The Method of Undetermined Coefficients I
We explore the solution of nonhomogeneous linear equations in the case
where the forcing function is the product of an exponential function and a
polynomial.
5.5 The Method of Undetermined Coefficients II
We explore the solution of nonhomogeneous linear equations with other forcing
functions.
5.6 Reduction of Order
We explore a technique for reducing a second order nonhomgeneous linear differential
equation to first order when we know a nontrivial solution to the complementary
homogeneous equation.
5.7 Variation of Parameters
We study the method of variation of parameters for finding a particular solution to a
nonhomogeneous second order linear differential equation.
6.1 Spring Problems I
We study undamped harmonic motion as an application of second order linear
differential equations.
6.2 Spring Problems II
We return to our study of harmonic motion as an application of second order
linear differential equations, this time considering the cases where damping
occurs.
6.3 The RLC Circuit
We study electric circuits as an application of second order linear differential
equations.
6.4 Motion Under A Central Force
We study the motion of a object moving under the influence of a central
force.
7.1 Review of Power Series
We review the basic properties of power series representation of functions.
7.2 Series Solutions Near an Ordinary Point I
We consider the utilization of power series to determine solutions to certain
differential equations.
7.3 Series Solutions Near an Ordinary Point II
We consider the utilization of power series to determine solutions to more general
differential equations.
7.4 Regular Singular Points: Euler Equations
We consider the utilization of power series to determine solutions to differential
equations near a singular point. We also study Euler equations.
7.1 The Method of Frobenius I
We begin our study of the method of Frobenius for finding series solutions of linear
second order differential equations.
7.6 The Method of Frobenius II
We continue our study of the method of Frobenius for finding series solutions of
linear second order differential equations, extending to the case where the indicial
equation has a repeated real root.
7.7 The Method of Frobenius III
We conclude our study of the method of Frobenius for finding series solutions of
linear second order differential equations, considering the case where the indicial
equation has distinct real roots that differ by an integer.
8.1 Introduction to the Laplace Transform
We begin our study of Laplace transforms with the definition, and we derive the
Laplace Transform of some basic functions.
8.2 The Inverse Laplace Transform
Given , the Laplace transform of some function , we study techniques for recovering
the function .
8.3 Solution of Initial Value Problems
We demonstrate how Laplace transforms can be used to solve constant coefficient
second order initial value problems.
8.5 Constant Coefficient Equations with Piecewise Continuous Forcing Functions
We show how Laplace Transforms may be used to solve initial value problems with
piecewise continuous forcing functions.
8.6 Convolution
We define the convolution of two functions, and discuss its application to computing
the inverse Laplace transform of a product.
8.7 Constant Coefficient Equations with Impulses
We study the solution of initial value problems where the external force is an
impulse.
9.1 Introduction to Linear Higher Order Equations
Given an th order linear differential equation, we discuss necessary and sufficient
conditions for a set of functions to be a fundamental set of solutions.
9.2 Higher Order Constant Coefficients Homogeneous Equations
We discuss the solution of an th order homogeneous linear differential equation.
9.3 Undetermined Coefficients for Higher Order Equations
We discuss the solution of an th order nonhomogeneous linear differential equation,
making use of the method of undetermined coefficients to find a particular
solution.
9.4 Variation of Parameters for Higher Order Equations
We discuss the solution of an th order nonhomogeneous linear differential equation,
making use of variation of parameters to find a particular solution.
10.2 Linear Systems of Differential Equations
We show how linear systems can be written in matrix form, and we make many
comparisons to topics we have studied earlier.
10.3 Basic Theory of Homogeneous Linear System
We study the theory of homogeneous linear systems, noting the parallels with the
study of linear homogeneous scalar equations.
10.5 Constant Coefficient Homogeneous Systems II
We continue our study of constant coefficient homogeneous systems. In this section
we consider the case where has real eigenvalues, but does not have linearly
independent eigenvectors.
10.7 Variation of Parameters for Nonhomogeneous Linear Systems
We study constant coefficient nonhomogeneous systems, making use of variation of
parameters to find a particular solution.