- #1

Repetit

- 128

- 2

Could someone please help me find out how to express the product of two Legendre polynomials in terms of a sum of Legendre polynomials. I believe I have to use the recursion formula

[tex](l+1)P_{l+1}(x)-(2l+1) x P_l(x) + l P_{l-1}(x)=0[/tex]

but I am not sure how to do this. What is basically want to do is

[tex]P_n(x) P_m(x) = \sum\limits_i c_i P_i(x)[/tex]

I hope my question is understandable.

Thanks!