yes I couldn't do this in exam, I try it in two way
* y= \sum_{n=\zero}^\infty C_nx^{(n+r)}} from this I found \frac {dy}{dx} and \frac {d^2y}{dx^2} and put them to equection and go on with frobenius method but I couldn't find "r" becouse of too many indicial equations so I couldn't find...