I'm trying to find the MLE based on a random sample $X_{1},...,X_{n}$ from this following distribution
$X_{i} \sim PAR(1,\kappa)$
This is my work so far
$$f(x;\kappa) = \frac{\kappa}{(1+x_{i})^{1+\kappa}}$$ $$L(\kappa) = \prod_{i=1}^{n} \frac{\kappa}{(1+x_{i})^{1+\kappa}}$$ $$\ln L = n \ln \kappa - (1+\kappa)\sum_{i=1}^{n} \ln (1+x_{i})$$ $$0 = \frac{\partial \ln L}{\partial \kappa} = \frac{n}{\kappa} - ... $$
I don't know how to continue can anyone help?