Finding an Integrating Factor for a Diffential Equation

Click For Summary
SUMMARY

The discussion focuses on finding an integrating factor for the differential equation (y^2 - xy)dx + (x^2 + xy)dy = 0, as presented in Boas' "Mathematical Methods in the Physical Sciences" (2nd Edition, Chapter 8.4, Problem 10). The original poster seeks strategies for identifying the integrating factor by inspection, expressing frustration with previous attempts that included dividing by xy and (xy)^2. The conversation highlights the importance of recognizing patterns and employing analytical techniques to simplify the process of finding integrating factors.

PREREQUISITES
  • Understanding of ordinary differential equations (ODEs)
  • Familiarity with integrating factors in differential equations
  • Knowledge of exact differential equations
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the method of finding integrating factors for first-order ODEs
  • Explore the concept of exact differential equations and their solutions
  • Practice solving differential equations using integrating factors
  • Review examples from Boas' "Mathematical Methods in the Physical Sciences"
USEFUL FOR

Mathematics students, educators, and anyone interested in mastering the techniques for solving ordinary differential equations, particularly those looking to enhance their skills in finding integrating factors.

aperception
Messages
12
Reaction score
0
Integrating Factors for ODEs (Question from Boas)

Find an integrating factor by inspection to make the below differential equation exact.

[itex](y^2-xy)dx+(x^2+xy)dy=0[/itex]

I've been inspecting, but I'm not seeing it! Is there a way to analyze this in my head that will lead me more easily to the integrating factor? I tried dividing by xy and (xy)^2 and a bunch of other things, but they didn't really get me anywhere.

Note this isn't actually for coursework, the original question is from Boas (2nd Edition, Ch 8.4, Problem 10), and asks to actually solve the differential equation, but I just want to practice finding integrating factors by inspection, so I modified the problem slightly.
 
Last edited:
Physics news on Phys.org
Anyone? I know there are lots of Boas lovers on here
 

Similar threads

Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
24
Views
3K
Replies
4
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 19 ·
Replies
19
Views
2K