Eigenfunction expansion in Legendre polynomials

hi10
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Homework Statement



How to use eigenfunction expansion in Legendre polynomials to find the bounded solution of
(1-x^2)f'' - 2xf' + f = 6 - x - 15x^2 on -1<= x <= 1

Homework Equations



eigenfunction expansion

The Attempt at a Solution



[r(x)y']' + [ q(x) + λ p(x) ] = f(x)
In this case, r = 1-x^2 , q = 1 , p = 0 , f = 6 - x -15 x^2 , r(-1) = r (1) = 0

Thanks for any help!
 

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First what are the eigenfunctions you want to use? In other words, what are the solutions to Legendre's equation.
 
I have the same problem.

the attachment from hi10 is what i was thinking.

Does anyone know what u(x) is in hi10's post for determining what an is?
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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