( ) Power series solution for ODE

In summary, it is important to examine the terms taken out of the sum and to possibly substitute the series solution back into the ODE in order to find the relationship between the coefficients b's.
  • #1
Deathcrush
40
0
(URGENT) Power series solution for ODE

Homework Statement



Supose there is an infinite series solution[tex]\sum b_{n}x^{n}[/tex] for

u''+4(x-(1/4))^2*u+C(x) = 0 where C(x) is a function (I get it in another problem, I'll put it in the relevant equations area), determinate the coefitients [tex]b_{0} b_{1} b_{2} b_{3} b_{4}[/tex]and express an approximate solution, use C to express the whole function in terms of r

Homework Equations



u''+4(x-(1/4))^2*u+C(x) = 0 the ODE

C(x)=(.3(e^r)(1-e^r)/r)
I am also given some initial conditions, but I don't think they are relevant for now

The Attempt at a Solution



I derived the proposed solution and used it in the ODE, then I changed the indexes and took some terms out of the sum so that I would get only one series, after that, I am supposed to get a relationship between the b's so that I can get those b's , but I don't seem to find it, since there are too many terms out of the sum. Any idea? this should be done for tomorrow :S
 
Last edited:
Physics news on Phys.org
  • #2


Hello,

Thank you for posting your question on the forum. I understand that you are working on finding the coefficients for the infinite series solution for the ODE u''+4(x-(1/4))^2*u+C(x) = 0, and you are having trouble finding the relationship between the coefficients b's. I would recommend taking a closer look at the terms that you have taken out of the sum and see if you can simplify them further. It is possible that there may be a common factor that can be factored out, which would make it easier to find the relationship between the coefficients. Additionally, you could try substituting the series solution back into the ODE and see if you can manipulate it to get a relationship between the coefficients. I hope this helps. Good luck with your assignment!
 

What is a power series solution for ODE?

A power series solution for ODE (ordinary differential equation) is a method of solving a differential equation by expressing the solution as an infinite series of powers of the variable. This allows for a more precise and accurate solution compared to other methods, especially for complex or non-linear equations.

How does a power series solution work?

A power series solution starts with a given differential equation and a starting point for the solution. The solution is then expanded as a sum of terms, each with a varying power of the variable. These terms are then plugged into the differential equation, and by equating coefficients of the same powers, a system of equations can be solved to determine the coefficients of the power series. This series can then be used to approximate the solution to the original differential equation.

What are the advantages of using a power series solution?

One of the main advantages of using a power series solution is its flexibility. It can be used to approximate solutions for a wide range of differential equations, including non-linear and non-homogeneous ones. Additionally, it provides a more accurate solution compared to other approximation methods, making it useful for solving complex problems in physics, engineering, and other scientific fields.

What are the limitations of a power series solution?

Although a power series solution can provide a more precise solution compared to other methods, it is not always possible to find an exact solution. In some cases, the series may not converge, meaning that the solution cannot be approximated using this method. Additionally, the series may require a large number of terms to achieve a desired level of accuracy, making it computationally intensive.

How can a power series solution be applied in real-world situations?

A power series solution has various applications in physics, engineering, and other scientific fields. It can be used to model and solve problems involving oscillations, heat transfer, fluid dynamics, and many other phenomena. It is also used in control systems and optimization problems, as well as in numerical methods for solving partial differential equations.

Similar threads

  • Calculus and Beyond Homework Help
Replies
7
Views
1K
  • Calculus and Beyond Homework Help
Replies
16
Views
558
  • Calculus and Beyond Homework Help
Replies
4
Views
493
Replies
1
Views
623
  • Calculus and Beyond Homework Help
Replies
2
Views
709
  • Calculus and Beyond Homework Help
Replies
1
Views
253
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
325
  • Calculus and Beyond Homework Help
Replies
3
Views
491
  • Calculus and Beyond Homework Help
Replies
7
Views
704
Back
Top