Difference between revisions of "Root-mean-square"

 
 
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The '''root-mean square''', or ''quadratic mean'', of any positive real numbers <math>x_1,\dots , x_n</math>, is
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The '''root-mean-square''' or ''quadratic mean'' of a collection of [[real number]]s <math>x_1,\dots , x_n</math> is defined to be <math>\sqrt{\frac{x^2_1+x^2_2+\dots+x^2_n}{n}}</math>.  This is the second [[power mean]] of the <math>x_i</math>.
  
<math>\sqrt{\frac{x^2_1+x^2_2+\dots+x^2_n}{n}}</math>
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It is so-named because it is the square root of the mean of the squares of the <math>x_i</math>.
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It is also part of the well-known [[Root-Mean Square-Arithmetic Mean-Geometric Mean-Harmonic mean Inequality]]
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== See Also ==
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* [[RMS-AM-GM-HM]] [[inequality]]
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* [[Power Mean Inequality]]
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Latest revision as of 13:41, 8 May 2013

The root-mean-square or quadratic mean of a collection of real numbers $x_1,\dots , x_n$ is defined to be $\sqrt{\frac{x^2_1+x^2_2+\dots+x^2_n}{n}}$. This is the second power mean of the $x_i$.

It is so-named because it is the square root of the mean of the squares of the $x_i$.

It is also part of the well-known Root-Mean Square-Arithmetic Mean-Geometric Mean-Harmonic mean Inequality

See Also

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