Solving a 2nd Order Linear ODE: Any Clever Tricks?

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SUMMARY

The discussion focuses on solving the second-order linear ordinary differential equation (ODE) given by $$ay''-(2x+1)y'+2y=0$$ with boundary conditions ##y(0)=1## and ##y(1)=0##, where ##a## is a non-zero constant. An analytic solution exists, confirmed through Mathematica, which utilizes the imaginary error function. A proposed method involves a change of variables with ##u=2x+1##, leading to a transformed equation suitable for power series expansion.

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Homework Statement


$$ay''-(2x+1)y'+2y=0$$ subject to ##y(0)=1## and ##y(1)=0## where ##a## is a non-zero constant.

Homework Equations


Not too sure

The Attempt at a Solution


I know an analytic solution exists since I solved with mathematica. My thoughts were to try a series expansion, but since the analytic solution is in closed form and is using the imaginary error function, I'd rather not waste a lot of time with a power series guess if someone knows (or sees) something insightful.

Any ideas or clever tricks?

Thanks!
 
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I would use two methods. First, let u= 2x+ 1. Then du/dx= 2 so [itex]dy/dx= (dy/du)(du/dx)= 2(dy/du)[/itex] and [itex]d^2y/dx^2= (d/dx)(dy/dx)= d/dx(2dy/du)= 4 d^2y/du^2[/itex]. So the equation becomes [itex]4\alpha d^2y/du^2- 2udy/d+ 2y= 0[/itex].

Now look for a power series solution. Let [itex]y= \sum_{n=0}^\infty a_nu^n[/itex].
Content abridged by a mentor.
 
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