Q5. Let $X_1, X_2, \dots, X_n$ be a random sample from $f_\theta(x) = \theta/x^{\theta+1}$, $1 \le x < \infty$.
(i) Find the maximum likelihood estimate for $\theta$.
(ii) Find the Cramer-Rao lower bound on the variance of an unbiased estimate of $\theta$.