Solve Dy/dx=x+y^2 | Integrating Factor & Rearrange

  • Thread starter Thread starter cerium
  • Start date Start date
Click For Summary

Homework Help Overview

The discussion revolves around solving the ordinary differential equation (ODE) dy/dx = x + y^2. Participants are exploring the applicability of integrating factors and methods for rearranging the equation to a linear form, while also identifying the nature of the equation as nonlinear.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are questioning whether an integrating factor can be used and if rearranging y^2 affects the equation's form. There is confusion about converting the nonlinear ODE into a linear one and whether other methods exist for this transformation.

Discussion Status

The discussion is ongoing, with some participants suggesting that the equation is a Riccati equation and exploring alternative methods. There is a lack of consensus on the best approach, but guidance has been offered regarding the nature of the equation and potential methods for solving it.

Contextual Notes

Participants note that the problem may be part of a specific class, indicating that the techniques learned in linear ODEs may not apply here. The nonlinear nature of the ODE is a point of discussion, with references to Riccati equations and second-order linear transformations.

cerium
Messages
15
Reaction score
0

Homework Statement



do I use the integrating factor for this question and if I do when i rearrange y^2 to the other side into the form of p(x)y does x become -1

Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org


The ODE is not linear, so the linear integrating factor you are most likely talking about does not apply (in the same way as you have learned). Are there other methods you have learned? Are there ways of converting an equation like this into a linear equation? Check and see what you can find. If you need more help, let us know.
 


Im really confused I thought I rearranged and moved the y^2 to the other side, I am I missing a really easy point, how could I change it to make it linear
 


You posted this in the homework section, so I would presume it is for some class. Which one? This certainly isn't the typical calc III type of problem. An ODE class, perhaps, but since this is a nonlinear ODE the techniques used to solve linear ODEs won't work here.

In fact, this is a Riccati equation.
 


solve z''+x*z=0?
 
Last edited:


if you take
<br /> y = -\frac{z&#039;}{z}<br />
then:
<br /> y&#039; = -\frac{z&#039;&#039;}{z} + \frac{(z&#039;)^2}{z^2}<br />
and your equation becomes of 2nd order, but a linear one:
<br /> z&#039;&#039; + x \, z = 0<br />
The solution for z is in terms of Airy functions.
 


solve z''+x*z=0 to find z?
 


ali salah mah said:
solve z''+x*z=0?

ali salah mah said:
solve z''+x*z=0 to find z?

Dickfore said:
if you take
<br /> y = -\frac{z&#039;}{z}<br />
then:
<br /> y&#039; = -\frac{z&#039;&#039;}{z} + \frac{(z&#039;)^2}{z^2}<br />
and your equation becomes of 2nd order, but a linear one:
<br /> z&#039;&#039; + x \, z = 0<br />
The solution for z is in terms of Airy functions.
what is the solution for [z′′+x*z=0]
 


what the solution for z in terms Airy functions for z′′+x*z=0 ?
 

Similar threads

  • · Replies 8 ·
Replies
8
Views
2K
Replies
4
Views
3K
Replies
7
Views
2K
Replies
7
Views
2K
  • · Replies 16 ·
Replies
16
Views
5K
Replies
4
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 2 ·
Replies
2
Views
974
Replies
3
Views
2K