Put the eigenvalue function in self-adjoint form

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The discussion centers on converting the differential equation \(-(1-x^{2})y'' + xy' = ky\) into self-adjoint form. The user identifies the integrating factor as \((x^{2}-1)^{1/2}\) and proposes the self-adjoint form as \(-\frac{d}{dx} \left( (1-x^{2})^{3/2} \frac{dy}{dx} \right) = k(x^{2}-1)^{1/2}\). They seek validation of their approach and inquire about transforming the equation into the form \(\frac{d^{2}y}{dx^{2}} = -ky\) using the substitution \(x = \cos(\theta)\). The discussion highlights the process of finding self-adjoint forms and the challenges in manipulating differential equations. Overall, the thread focuses on the mathematical techniques for achieving the desired equation format.
GGGGc
Homework Statement
The original equation is -(1-x^(2))y’’+xy’=ky. How to put it in self-adjoint form?
Also, if let x=cos(theta) how to put that form in d^(2)y/dx^(2)=-ky form?
Relevant Equations
-(1-x^(2))y’’+xy’=ky
Here’s my work:
The integrating factor I find is (x^(2)-1)^1/2. The self adjoint form I find is
-d/dx (((1-x^(2))^(3/2))*dy/dx))=k(x^(2)-1)^(1/2).
Am I right?
 
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The left hand side is of the form <br /> -u^2y&#039;&#039; - uu&#039;y&#039; = -u(uy&#039;)&#039; for some u.
 
GGGGc said:
Homework Statement: The original equation is -(1-x^(2))y’’+xy’=ky. How to put it in self-adjoint form?
Also, if let x=cos(theta) how to put that form in d^(2)y/dx^(2)=-ky form?
Relevant Equations: -(1-x^(2))y’’+xy’=ky

Here’s my work:
The integrating factor I find is (x^(2)-1)^1/2. The self adjoint form I find is
-d/dx (((1-x^(2))^(3/2))*dy/dx))=k(x^(2)-1)^(1/2).
Am I right?
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