Linear Differential Equation to solve?

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SUMMARY

The discussion focuses on solving a Cauchy's Linear Differential Equation (LDE) represented by the equation x²y'' + 3xy' + y = 1/(1-x)². The user initially substitutes x = e^t, transforming the equation into a more manageable form. The characteristic equation derived is Yc = (c1 + c2x)e^-1. The main challenge lies in finding the Particular Integral (Yp), which is proposed as Yp = 1/{(D+1)²(1+e^t)²}. The solution involves using methods such as reduction of order and variation of parameters to address the nonhomogeneous part of the equation.

PREREQUISITES
  • Cauchy’s Linear Differential Equations
  • Substitution methods in differential equations
  • Characteristic equations and their solutions
  • Variation of parameters technique
NEXT STEPS
  • Study the method of reduction of order for solving differential equations
  • Learn about variation of parameters in the context of nonhomogeneous differential equations
  • Explore the characteristics of Euler's differential equations
  • Practice solving Cauchy’s LDE with different nonhomogeneous terms
USEFUL FOR

Students and educators in mathematics, particularly those studying differential equations, as well as anyone looking to deepen their understanding of Cauchy’s LDE and related solution techniques.

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Homework Statement



this is Cauchy's LDE.. someone help me to solve this equation.

x^2 y'' + 3x y' + y = 1/(1-x)^2

Homework Equations


The Attempt at a Solution



i started it with substituting
x= e^t
then ln x = t
and d/dt = D

hence the equation becomes

{ D(D-1) +3D +1} y = 1/(1+e^t)^2

and i got characteristics equation
as
Yc=(c1 + c2x ) e^-1

now i have problem in findind Particular Intergral i-e Yp..

i-e
Yp = 1 / {(D+1)^2 (1+e^t)^2 } ?

somebody help to complete its solution?
 
Last edited:
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I've only seen that sort of equation referred to as an Euler's differential equation. See, e.g., http://mathworld.wolfram.com/EulerDifferentialEquation.html.

You solve the homogeneous equation by substituting y = x^n and finding appropriate values for n. (In your case, you run into a double root, so you'll have to use reduction of order to find the second solution.) Then you can use variation of parameters to find the solution to the nonhomogeneous equation.
 
thanks Obafgkmrns... i got it..
 

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