The first thing is that has to formatted in a way that can be read. Do you know how to use latex?

First of all what is P^2(n)(x)? The Legendre polynomials? Did I interpret your problem correctly in my latex?

]]>upto this i followed but after that last step the book which i am refering gives answer =2÷(2n+1)

can u just help me how to come to that answer.. plz give me steps to follow..]]>