We choose $I = [-1,1]$ and fix any very good extremal pair $(Q, R)$. We set $P = QR$. Deduce from question 4.41 that: $$\left(1 - X^2\right)P'' - XP' + (n+m)^2 P = 0$$
We choose $I = [-1,1]$ and fix any very good extremal pair $(Q, R)$. We set $P = QR$. Deduce from question 4.41 that:
$$\left(1 - X^2\right)P'' - XP' + (n+m)^2 P = 0$$