Second order homog. DE non-const coeff.

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The discussion revolves around solving a second-order homogeneous linear differential equation with non-constant coefficients, specifically verifying that y(x) = sin(x^2) is in the kernel of the operator L defined as L = D^2 - x^(-1)D + 4x^2. The user attempts to apply the operator to y and ends up with the equation y'' - x^(-1)y' + 4x^2y = 0 but feels stuck. A suggestion is made to simply substitute sin(x^2) into the equation to verify the solution. The conversation also includes light-hearted comments about needing sleep.
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I have a 2nd order homogeneous non-const. coefficients linear DE, and don't remember how we used to solve it or even if we did at all, looked through the book, but it only covers a case of Cauchy-Euler.

The original question actually goes like this:
verify that y(x) = sin (x2) is in the kernel of L,
L = D2 - x-1D + 4x2, where D is a differetiation operator.

so what I have so far is this:
Ly = 0
when I distribute I get this DE and get stuck with it:

y'' - x-1y' + 4x2y = 0

Thanks for any help.
 
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EvLer said:
The original question actually goes like this:
verify that y(x) = sin (x2) is in the kernel of L,
L = D2 - x-1D + 4x2, where D is a differetiation operator.

so what I have so far is this:
Ly = 0
when I distribute I get this DE and get stuck with it:

y'' - x-1y' + 4x2y = 0

Thanks for any help.
This is a very simple question, just insert sin(x^2) for y.

ehild
 
shoot...i need sleep.

Thanks :smile:
 
EvLer said:
shoot...i need sleep.

Thanks :smile:

Good night, sleep tight! :zzz:

ehild
 
sleep...highly recommended
 
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