## Upper and Lower Bound eigenvalues Sturm Liouville Problem HELP

Hi anyone, any idea how to solve this problem. I really got stuck.

01. Find upper and lower bounds for the kth eigenvalues $\lambda_k$ of the problem
$((1+x^2)u')'-xu+\lambda(1+x^2)u=0$ for $0 < x < 1$ with boundary conditions $u(0)=0;u(1)=0$

Many thanks.