Trying to solve a second order ODE

Therefore, y(x) = h(x)/x = sinx/x.In summary, the conversation discusses solving a second order ODE for y(x) using the substitution y(x)=h(x)/x. The general solution for h(x) is found to be h(x)=A sin(x) + B cos(x), which can be substituted into the original equation for y(x) to get y(x)=(A sin(x) + B cos(x))/x. The final step is to use the initial condition y(0)=1 to determine A and B, although there is confusion about this since y is singular at x=0.
  • #1
cahill8
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0

Homework Statement



I'm trying to solve a second order ODE for [tex]y(x)[/tex] to show that the solution is [tex]y(x)=sin(x)/x[/tex]. We've been told to use the substitution [tex]y(x)=h(x)/x[/tex]. I've got to the stage of solving for [tex]h(x)[/tex], arriving at [tex]h''(x)=-x[/tex]. Using the general solution, [tex]h(x)=A sin(x) + B cos(x)[/tex] and substiting this into the original equation for [tex]y(x)[/tex] I get [tex]y(x)=(A sin(x) + B cos(x))/x[/tex]

So all that's left to do it seems is to use the inital conditions to show A=1 and B=0 however the problem says to use the inital condition [tex]y(0)=1[/tex]. This doesn't make sense to me since y is singular at x=0. Is this inital condition a mistake or am I missing something?


Homework Equations


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The Attempt at a Solution


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  • #2
hi cahill8! :smile:

limx->0 sinx/x = 1 :wink:
 

FAQ: Trying to solve a second order ODE

What is a second order ODE?

A second order ODE (ordinary differential equation) is a mathematical equation that involves a function, its first derivative, and its second derivative. It describes the relationship between a variable and its rate of change over time.

How do you solve a second order ODE?

To solve a second order ODE, you need to use techniques such as separation of variables, integrating factors, or series solutions. The exact method used depends on the specific form of the equation and the initial/boundary conditions given.

Why are second order ODEs important?

Second order ODEs are important because they have many real-world applications, such as in physics, engineering, and economics. They are used to model and analyze systems that involve rates of change, making them essential in understanding and predicting real-world phenomena.

What are the main challenges in solving a second order ODE?

The main challenges in solving a second order ODE are identifying the appropriate method or technique to use, dealing with complex or nonlinear equations, and finding the right initial/boundary conditions. It also takes a lot of practice and experience to become proficient in solving these types of equations.

Can a second order ODE have multiple solutions?

Yes, a second order ODE can have multiple solutions. This is because the solutions can depend on the initial/boundary conditions and the specific form of the equation. In some cases, there may be an infinite number of solutions, while in others, there may be a finite number of distinct solutions.

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