Solving 2nd order differential equation

In summary, the conversation discusses solving a differential equation and determining the inhomogeneous solution using the method of undetermined coefficients. The solution is verified by checking if it satisfies the original differential equation.
  • #1
Pushoam
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Homework Statement


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Homework Equations

The Attempt at a Solution



For the homogeneous equation, I have got the the root of the characteristic equation as ## e^{ix}, e^{-ix} ## .

So, the corresponding solution is ## B \sin{ x} + A \cos{ x} ## .

Then, I took the particular solution as C.

Putting C in the differential equation , I get C = -1.

So, the inhomogeneous solution is ## A \cos{ x} + B \sin{ x} – 1 ## , i.e. option(e).

Is this correct?
 

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  • #2
Looks great. You can plug it into the original differential equation to make sure that your solution satisfies it.
 
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  • #3
Pushoam said:
So, the inhomogeneous solution is ## A \cos{ x} + B \sin{ x} – 1 ## , i.e. option(e).
Is this correct?
You shouldn't need to ask this. Along the lines of @scottdave's advice, whenever you get a solution to a diff. equation, you should get in the habit of checking. That way you'll know whether your answer is correct. For an initial value problem, check that 1) your solution satisfies the initial condition, and 2) your solution satisifies the differential equation.
 
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FAQ: Solving 2nd order differential equation

1. What is a 2nd order differential equation?

A 2nd order differential equation is a mathematical equation that involves the second derivative of a function. It is typically used to describe the behavior of a physical system over time.

2. How do you solve a 2nd order differential equation?

To solve a 2nd order differential equation, you must first identify the type of equation (linear, non-linear, etc.) and then apply the appropriate methods, such as separation of variables, variation of parameters, or Laplace transforms.

3. What is the difference between homogeneous and non-homogeneous 2nd order differential equations?

A homogeneous 2nd order differential equation has all terms containing the dependent variable and its derivatives, while a non-homogeneous equation has additional terms that do not involve the dependent variable or its derivatives.

4. Can a 2nd order differential equation have multiple solutions?

Yes, a 2nd order differential equation can have multiple solutions. This is because the general solution of a 2nd order equation contains two arbitrary constants, allowing for a variety of possible solutions.

5. What are some real-life applications of 2nd order differential equations?

2nd order differential equations are commonly used in physics, engineering, and other fields to model and predict the behavior of physical systems. They can be used to describe motion, heat transfer, population growth, and many other phenomena.

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