So the equality is that given r > s and x_1, x_2, \ldots x_n \epsilon \; \Re where s \geq 0 if any of the x_1, x_2, \ldots x_n = 0. Then:
P(r) \geq P(s)
where P(r) = \left \{ {\begin{array}{*{20}c}
{(\frac{x_1^r + x_2^r \ldots + x_n^r}{n})^{1/r},} & {r \neq 0} \\...