Question: Show that $(\frac{1}{n} \sum_{i=1}^n |x_i|^p)^{1/p} \ge \frac{1}{n} \sum_{i=1}^n |x_i|$ in which $p>1$, $x_i \in \mathbb{R}$, $i=1,2,\dots,n$
Could you give me some hint to solve this problem. I see that it like the Minkovski's inequality but it not true. Thank all!