I am having trouble with a simple question : Consider $\bar{R}$ the extended real line and $ 0 < q < \infty$.
Let $x_n $a sequence in $\bar{R}$ with $x_n \geq 0, \forall \ n $. Suppose that $x_n \rightarrow a$ where $a = + \infty$
What I can say about the limit below?
$lim_{n \rightarrow + \infty} (x_n)^{\frac{-1}{q}}$