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Power Mean Inequality

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The Power Mean Inequality is a generalized form of the multi-variable Arithmetic Mean-Geometric Mean Inequality.

Inequality

For real numbers k_1,k_2 and positive real numbers a_1, a_2, \ldots, a_n, k_1\ge k_2 implies the k_1th power mean is greater than or equal to the k_2th.

Algebraically, k_1\ge k_2 implies that \left( \frac{\sum\limits_{i=1}^n a_{i}^{k_1}}{n} \right) ^ {\frac{1}{k_1}}\ge \left( \frac{\sum\limits_{i=1}^n a_{i}^{k_2}}{n...

The Power Mean Inequality follows from the fact that \frac{\partial M(t)}{\partial t}\geq 0 (where M(x) is the tth power mean) together with Jensen's Inequality.

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