How to solve x^2 y' + 2xy = arctan(x) - ODE

  • Thread starter Thread starter Lodve
  • Start date Start date
  • Tags Tags
    Ode
Click For Summary
SUMMARY

The discussion focuses on solving the differential equation x^2y' + 2xy = arctan(x). The user initially transformed the equation into a first-order linear form by dividing both sides by x^2 and then applied the integrating factor e^(2lnx). The key step involves recognizing that the left side represents the derivative d/dx(x^2y), leading to the integral x^2y = ∫arctan(x) dx. To solve the integral on the right side, integration by parts is recommended.

PREREQUISITES
  • Understanding of first-order linear differential equations
  • Familiarity with integration techniques, specifically integration by parts
  • Knowledge of the arctangent function and its properties
  • Proficiency in manipulating exponential functions and logarithms
NEXT STEPS
  • Study the method of integration by parts in detail
  • Explore the properties and applications of arctan(x) in calculus
  • Review first-order linear differential equations and their solutions
  • Practice solving similar differential equations using integrating factors
USEFUL FOR

Students and professionals in mathematics, particularly those studying differential equations, as well as educators looking for examples of solving first-order linear differential equations.

Lodve
Messages
11
Reaction score
0
I struggle to solve this Differential equation:
x^2y' +2xy = arctanx
What I did was just divide x^2 on both side of the sign of equality in order to get the same form as a first-order linear diff.equation. After I've done that, I just multiply e^(2lnx) on the both side of the equation so that the left side of the equation can be written in the form of (u*v)'. Now I basically integer on the both side of the equation to remove the derive sign on the left side, but I struggle to integer on the right side of the equation. Can somebody here help me continueing solving this diff.equation? :D
 
Physics news on Phys.org


In the original problem, the left side is the derivative of x2y. So you have
d/dx(x2y) = tan-1(x)
==> x2y = \int tan^{-1}(x) dx

You can use integration by parts to integrate the right side.
 

Similar threads

Replies
4
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
7
Views
2K
Replies
11
Views
2K
Replies
9
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
22
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K